Merge pull request #21 from ncsaba/wdb-wrapper

wdb wrapper
Merge pull request #22 from ncsaba/wdb-wrapper

Wdb wrapper
Merge pull request #23 from ncsaba/wdb-wrapper

Wdb wrapper
Merge pull request #24 from ncsaba/wdb-wrapper

added Extrude primitive wrapper
Merge pull request #25 from ncsaba/wdb-wrapper

Wdb wrapper
Added options to cache bindings for re-installation (helps shrotening the install time when working on higher level features)
Merge pull request #1 from raj12lnm/master

Add VOL primitive - thanks Raj !
Adding VOL primitive - cosmetic fixes
Merge pull request #26 from ncsaba/master

added brlcad._bindings.BRLCAD_VERSION; conditionally add HRT primitive;
fix install when the 'cached-reinstall' parameter is missing from python-brlcad.cfg
fix small _bindings/ caching problems
Add ASCII-art docs to ARB8 primitive
added Vector methods: wrap, has_norm, is_parallel_to
WDB.ls accepts now glob-like <pattern> parameter
added ascii-art docs to plane.py
added Arc and Triangle objects to vmath package
enhance ascii-art docs in plane.py