merge revision(s) 46360,46372: [Backport #8625]

	* io.c (io_setstrbuf, io_read): should not shorten the given buffer until
	  read succeeds.  [ruby-core:55951] [Bug #8625]

	* io.c (read_all): truncate the buffer before appending read data,
	  instead of truncating before reading.
	  [ruby-core:55951] [Bug #8625]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@46738 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
merge revision(s) 45495: [Backport #9662]

	* README.EXT: fix typo.
  [ruby-core:61634] [Bug #9662]

	* README.EXT.ja: ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@46739 b2dd03c8-39d4-4d8f-98ff-823fe69b080e