Stix ipwatch v1.11

Adds support for STIX-based indicators for feature #1095.

From previous PR: #1096:
Ensured each commit compiles.
Modified WatchListData data structure in util-ipwatchlist.h to use a char* instead of a Signature.
Resolved comments from #1096 

From previous PR: #1060:
Organized and updated unit test function names to start with upper case letter in detect-watchlist.c and detect-smtp-indicators.c.
Modified InitWatchDataFully to properly invoke free.
Updated to meet QA standards.

Can you elaborate this?
Your recommendation is to lock the mutex here after being initialized?  When would it get unlocked then?  There is no access to the data structure's fields in this method.  I don't see the difference to other areas of the code, ex counters.c::265.