Backport of astobj2 ref/unref from astTrunk.c (references #2, references #22, references #15, references #6)

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4206 43c1dc8c-776e-4df2-8ef1-6e829299be21
Make compile against asterisk-1.6 (references #18)

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4207 43c1dc8c-776e-4df2-8ef1-6e829299be21