Add ARGV constant. It is not required by ISO. Compatibility with CRuby.

Fix a memory leak in mirb

Add "test runner" support for cross builds.

Change mruby-random License to MIT

refs: http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/MT2002/license.html

Fix checking for heredoc in mirb

Support $0 variable.

 "test runner" means target simulator like QEmu, GDB sim, and so on. Also "test runner" might be debug agents for real targets.
If you do not setup test_runner, Rake will work same as before.

stdint header seems required on osx for uint8_t

Define isascii for C99

Improve checking for unterminated string in mirb

Modified build dependency to exclude 'LEGAL' from libmruby archive.

Fix exit

Improve recent CRuby rake compatibility

Add syntax error for incomplete global variables

Add syntax error for incomplete instance/class variables

Support NameError#name

Add `NameError#name`. Fix `NameError.new` and `NameError.initialize`. Enable 2nd argument for `NameError.new` in C API.