Merge pull request #533 from jam7/update-glibc223

Add new experimental package named glibc223 to support glibc-2.23

packages/glibc223.rb

+require 'package'
+
+class Glibc223 < Package
+  version '2.23'
+  binary_url ({
+    armv7l: 'https://github.com/jam7/chromebrew/releases/download/newtoolchains/glibc-2.23-chromeos-armv7l.tar.xz',
+    i686:   'https://github.com/jam7/chromebrew/releases/download/newtoolchains/glibc-2.23-chromeos-i686.tar.xz',
+    x86_64: 'https://github.com/jam7/chromebrew/releases/download/newtoolchains/glibc-2.23-chromeos-x86_64.tar.xz',
+  })
+  binary_sha1 ({
+    armv7l: '4cac7d5d3d97f147c9ac9ad0c1deb1ac9b967450',
+    i686:   '434adb6dd1c3dcc30a25e3700f425a081888a28a',
+    x86_64: '9b4ae8c6ccc081f7d9d169cd0b3eb74ae736e79f',
+  })
+end