Revert [16614] and [16614]. Deal with plural form issues in early 3.2 and...

Revert [16614] and [16614]. Deal with plural form issues in early 3.2 and remove the hacks from Twenty Ten. see #13651.

git-svn-id: https://core.svn.wordpress.org/trunk@17111 1a063a9b-81f0-0310-95a4-ce76da25c4cd