Fix pbx_builtin_setlanguage to not seg when data is a NULL ptr. Also fix AGI...

Fix pbx_builtin_setlanguage to not seg when data is a NULL ptr.  Also fix AGI so we dont run into this with other specific problems as well. (bug 2641)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@3990 65c4cc65-6c06-0410-ace0-fbb531ad65f3