stasis: use ao2_t_alloc for certain object allocators

Add tags to stasis objects using the name.  This makes it
easier to track the source of certain stasis ref leaks.

Review: https://reviewboard.asterisk.org/r/3821/
........

Merged revisions 418996 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@418997 f38db490-d61c-443f-a65b-d21fe96a405b