AO2: Add an assert for bad objects

This adds an assert that will only be active if Asterisk is compiled
with DO_CRASH and allows the testsuite to fail tests that would
otherwise require log file parsing.
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Merged revisions 409566 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 409567 from http://svn.asterisk.org/svn/asterisk/branches/11
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Merged revisions 409568 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@409569 65c4cc65-6c06-0410-ace0-fbb531ad65f3