update licensing issue and how to contribute

COPYING

-mruby is copyrighted free software by mruby developers <info@mruby.org>.
-You can redistribute it and/or modify it under either the terms of the
-MIT license (see the file MITL), or the conditions below:
-
-  1. You may make and give away verbatim copies of the source form of the
-     software without restriction, provided that you duplicate all of the
-     original copyright notices and associated disclaimers.
-
-  2. You may modify your copy of the software in any way, provided that
-     you do at least ONE of the following:
-
-       a) place your modifications in the Public Domain or otherwise
-          make them Freely Available, such as by posting said
-          modifications to Usenet or an equivalent medium, or by allowing
-          the author to include your modifications in the software.
-
-       b) use the modified software only within your corporation or
-          organization.
-
-       c) give non-standard binaries non-standard names, with
-          instructions on where to get the original software distribution.
-
-       d) make other distribution arrangements with the author.
-
-  3. You may distribute the software in object code or binary form,
-     provided that you do at least ONE of the following:
-
-       a) distribute the binaries and library files of the software,
-          together with instructions (in the manual page or equivalent)
-          on where to get the original distribution.
-
-       b) accompany the distribution with the machine-readable source of
-          the software.
-
-       c) give non-standard binaries non-standard names, with
-          instructions on where to get the original software distribution.
-
-       d) make other distribution arrangements with the author.
-
-  4. You may modify and include the part of the software into any other
-     software (possibly commercial).  But some files in the distribution
-     are not written by the author, so that they are not under these terms.
-
-     For the list of those files and their copying conditions, see the
-     file LEGAL.
-
-  5. The scripts and library files supplied as input to or produced as
-     output from the software do not automatically fall under the
-     copyright of the software, but belong to whomever generated them,
-     and may be sold commercially, and may be aggregated with this
-     software.
-
-  6. THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
-     IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
-     WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-     PURPOSE.

COPYING.ja

-本プログラムはフリーソフトウェアです．MITライセンス
-または以下に示す条件で本プログラムを再配布できます
-MITライセンスについてはMTILファイル(参考訳:MITL.ja)を
-参照して下さい．
-
-  1. 複製は制限なく自由です．
-
-  2. 以下の条件のいずれかを満たす時に本プログラムのソースを
-     自由に変更できます．
-
-     (a) ネットニューズにポストしたり，作者に変更を送付する
-         などの方法で，変更を公開する．
-
-     (b) 変更した本プログラムを自分の所属する組織内部だけで
-         使う．
-
-     (c) 変更点を明示したうえ，ソフトウェアの名前を変更する．
-         そのソフトウェアを配布する時には変更前の本プログラ
-         ムも同時に配布する．または変更前の本プログラムのソー
-         スの入手法を明示する．
-
-     (d) その他の変更条件を作者と合意する．
-
-  3. 以下の条件のいずれかを満たす時に本プログラムをコンパイ
-     ルしたオブジェクトコードや実行形式でも配布できます．
-
-     (a) バイナリを受け取った人がソースを入手できるように，
-         ソースの入手法を明示する．
-
-     (b) 機械可読なソースコードを添付する．
-
-     (c) 変更を行ったバイナリは名前を変更したうえ，オリジナ
-         ルのソースコードの入手法を明示する．
-
-     (d) その他の配布条件を作者と合意する．
-
-  4. 他のプログラムへの引用はいかなる目的であれ自由です．た
-     だし，本プログラムに含まれる他の作者によるコードは，そ
-     れぞれの作者の意向による制限が加えられる場合があります．
-
-     それらファイルの一覧とそれぞれの配布条件などに付いては
-     LEGALファイルを参照してください．
-
-  5. 本プログラムへの入力となるスクリプトおよび，本プログラ
-     ムからの出力の権利は本プログラムの作者ではなく，それぞ
-     れの入出力を生成した人に属します．また，本プログラムに
-     組み込まれるための拡張ライブラリについても同様です．
-
-  6. 本プログラムは無保証です．作者は本プログラムをサポート
-     する意志はありますが，プログラム自身のバグあるいは本プ
-     ログラムの実行などから発生するいかなる損害に対しても責
-     任を持ちません．

LEGAL

@@ -2,7 +2,7 @@ LEGAL NOTICE INFORMATION
 ------------------------
 
 All the files in this distribution are covered under the MIT license
-(see the file COPYING) except some files mentioned below:
+(see the file MITL) except some files mentioned below:
 
 
 (Currently no items are listed.)

README

@@ -68,7 +68,7 @@ See the file INSTALL.
 
 * Copying
 
-See the file COPYING.
+See the file MITL.
 
 
 * About Contribution

README.ja

@@ -77,7 +77,7 @@ INSTALL.ja ファイルを参照してください。
 
 * 配布条件
 
-COPYING.ja ファイルを参照してください。
+MITL.ja ファイルを参照してください。
 
 
 * コントリビュートについて

README.md

@@ -69,14 +69,30 @@ To subscribe to the mruby mailing list....[T.B.D.]
 See the INSTALL file.
 
 
-## Copying
+## License
 
-See the COPYING file.
+Copyright (c) 2012 mruby developers
 
+Permission is hereby granted, free of charge, to any person obtaining a 
+copy of this software and associated documentation files (the "Software"), 
+to deal in the Software without restriction, including without limitation 
+the rights to use, copy, modify, merge, publish, distribute, sublicense, 
+and/or sell copies of the Software, and to permit persons to whom the 
+Software is furnished to do so, subject to the following conditions:
 
-## About Contribution
+The above copyright notice and this permission notice shall be included in 
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
+DEALINGS IN THE SOFTWARE.
+
+## Note for License
 
-Thank you for considering contributing to mruby.
 mruby has chosen a MIT License due to its permissive license allowing
 developers to target various environments such as embedded systems.
 However, the license requires the display of the copyright notice and license
@@ -90,18 +106,10 @@ In the future, mruby might ask you to distribute your new code
 (We did not intend for contributors to transfer or waive their copyrights,
  Actual copyright holder name (contributors) will be listed in the AUTHORS file.)
 
-Please ask us if you want to distribute your code under another license
-or if your code is derived from GPL code.
-
-
-## The Author
-
-See the file AUTHORS.
-
-
-Feel free to send comments and bug reports to the author. Here is the
-author's latest mail address:
-
-  devel@mruby.org
+Please ask us if you want to distribute your code under another license.
 
+## How to Contribute
 
+Send pull request to <http://github.com/mruby/mruby>.   We consider you have granted
+non-exclusive right to your contributed code under MIT license.  If you want to be named
+as one of mruby developers, include update to the AUTHORS file in your pull request.