Prepare for removal of DBGet/DBPut manager commands, by allowing Getvar to get...

Prepare for removal of DBGet/DBPut manager commands, by allowing Getvar to get functions (Setvar can already set functions)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@8078 65c4cc65-6c06-0410-ace0-fbb531ad65f3