Add extra doc to FILES section in nghttpx man pages

doc/h2load.1

 .\" Man page generated from reStructuredText.
 .
-.TH "H2LOAD" "1" "January 10, 2015" "0.7.1-DEV" "nghttp2"
+.TH "H2LOAD" "1" "January 11, 2015" "0.7.1-DEV" "nghttp2"
 .SH NAME
 h2load \- HTTP/2 benchmarking tool
 .

doc/nghttp.1

 .\" Man page generated from reStructuredText.
 .
-.TH "NGHTTP" "1" "January 10, 2015" "0.7.1-DEV" "nghttp2"
+.TH "NGHTTP" "1" "January 11, 2015" "0.7.1-DEV" "nghttp2"
 .SH NAME
 nghttp \- HTTP/2 experimental client
 .

doc/nghttpd.1

 .\" Man page generated from reStructuredText.
 .
-.TH "NGHTTPD" "1" "January 10, 2015" "0.7.1-DEV" "nghttp2"
+.TH "NGHTTPD" "1" "January 11, 2015" "0.7.1-DEV" "nghttp2"
 .SH NAME
 nghttpd \- HTTP/2 experimental server
 .

doc/nghttpx.1

 .\" Man page generated from reStructuredText.
 .
-.TH "NGHTTPX" "1" "January 10, 2015" "0.7.1-DEV" "nghttp2"
+.TH "NGHTTPX" "1" "January 11, 2015" "0.7.1-DEV" "nghttp2"
 .SH NAME
 nghttpx \- HTTP/2 experimental proxy
 .
@@ -225,6 +225,15 @@ HTTP/2  or  SPDY  proxy  mode  (\-s  option),  use
 .sp
 Default: \fB0\fP
 .UNINDENT
+.INDENT 0.0
+.TP
+.B \-\-rlimit\-nofile=<N>
+Set maximum number  of open files (RLIMIT_NOFILE)
+to <N>.  If 0 is  given, nghttpx does not set the
+limit.
+.sp
+Default: \fB0\fP
+.UNINDENT
 .SS Timeout:
 .INDENT 0.0
 .TP
@@ -733,6 +742,25 @@ Print this help and exit.
 The default configuration file path nghttpx searches at startup.
 The configuration file path can be changed using \fI\%\-\-conf\fP
 option.
+.sp
+Those lines which are staring \fB#\fP are treated as comment.
+.sp
+The option name in the configuration file is the long command\-line
+option name with leading \fB\-\-\fP stripped (e.g., \fBfrontend\fP).  Put
+\fB=\fP between option name and value.  Don\(aqt put extra leading or
+trailing spaces.
+.sp
+The options which do not take argument in the command\-line \fItake\fP
+argument in the configuration file.  Specify \fByes\fP as an argument
+(e.g., \fBhttp2\-proxy=yes\fP).  If other string is given, it is
+ignored.
+.sp
+To specify private key and certificate file which are given as
+positional arguments in commnad\-line, use \fBprivate\-key\-file\fP and
+\fBcertificate\-file\fP\&.
+.sp
+\fI\%\-\-conf\fP option cannot be used in the configuration file and
+will be ignored if specified.
 .UNINDENT
 .SH SIGNALS
 .INDENT 0.0

doc/nghttpx.1.rst

@@ -188,6 +188,14 @@ Performance:
 
     Default: ``0``
 
+.. option:: --rlimit-nofile=<N>
+
+    Set maximum number  of open files (RLIMIT_NOFILE)
+    to <N>.  If 0 is  given, nghttpx does not set the
+    limit.
+
+    Default: ``0``
+
 
 Timeout:
 ~~~~~~~~
@@ -644,6 +652,25 @@ FILES
   The configuration file path can be changed using :option:`--conf`
   option.
 
+  Those lines which are staring ``#`` are treated as comment.
+
+  The option name in the configuration file is the long command-line
+  option name with leading ``--`` stripped (e.g., ``frontend``).  Put
+  ``=`` between option name and value.  Don't put extra leading or
+  trailing spaces.
+
+  The options which do not take argument in the command-line *take*
+  argument in the configuration file.  Specify ``yes`` as an argument
+  (e.g., ``http2-proxy=yes``).  If other string is given, it is
+  ignored.
+
+  To specify private key and certificate file which are given as
+  positional arguments in commnad-line, use ``private-key-file`` and
+  ``certificate-file``.
+
+  :option:`--conf` option cannot be used in the configuration file and
+  will be ignored if specified.
+
 SIGNALS
 -------
 

doc/nghttpx.h2r

@@ -6,6 +6,25 @@ FILES
   The configuration file path can be changed using :option:`--conf`
   option.
 
+  Those lines which are staring ``#`` are treated as comment.
+
+  The option name in the configuration file is the long command-line
+  option name with leading ``--`` stripped (e.g., ``frontend``).  Put
+  ``=`` between option name and value.  Don't put extra leading or
+  trailing spaces.
+
+  The options which do not take argument in the command-line *take*
+  argument in the configuration file.  Specify ``yes`` as an argument
+  (e.g., ``http2-proxy=yes``).  If other string is given, it is
+  ignored.
+
+  To specify private key and certificate file which are given as
+  positional arguments in commnad-line, use ``private-key-file`` and
+  ``certificate-file``.
+
+  :option:`--conf` option cannot be used in the configuration file and
+  will be ignored if specified.
+
 SIGNALS
 -------