Make the second (taxonomy) parameter for get_term_link() optional if you pass...

Make the second (taxonomy) parameter for get_term_link() optional if you pass in a term object as the first argument (which has the taxonomy in it). fixes #13081. props scribu

git-svn-id: https://core.svn.wordpress.org/trunk@15586 1a063a9b-81f0-0310-95a4-ce76da25c4cd