AEntityFactory:
- account for structured sequences when constructing vertex-element
adjacencies (has to use different function for getting connectivity in
case of structured element)
- check for returned error when constructing vertex-element
adjacencies

MBCN:
- add function SubEntityConn, which returns the connectivity of a
given sub-entity given the parent connectivity and the sub-entity
dimension and index
- rename previous SubEntityConn function to SubEntityVertexIndices to
more accurately reflect function's purpose

MBTagConventions.hpp:
- add comments describing semantics of each tag type

WriteSLAC:
- added initializations to avoid compiler warnings

WriteVtk.cpp:
- removed a few newline outputs

TSTT/MBMesh.cpp:
- changed code in CreateEntities to be (much) more efficient, by not
using mb_range_inserter for vertices
- fixed a few dumb paste-os

TSTT/server/TSTT_MOAB_MoabMesh_Impl.cc:
- implemented entity set subtract/unite/intersect, entity
...