merge revision(s) r46899,r46903,r46904:

	split assertions into algorithms

	CentOS 7 seems finish MD5 support
	http://chkbuild005.hsbt.org/chkbuild/ruby-trunk/log/20140722T140010Z.fail.html.gz

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_1@46908 b2dd03c8-39d4-4d8f-98ff-823fe69b080e