Merge pull request #42 from mapzen/dwn

Adjacency List Updates
first pass at adding lua
added lua class
Check that we are not at the end of the bucket list when
clearing (was causing a crash).
erge remote-tracking branch 'origin' into lua

Conflicts:
	src/mjolnir/pbfgraphbuilder/pbfgraphbuilder.cc
added LuaTagTransform class.  Added lua parsing logic.
removed pbfgraphbuilder
Merge pull request #43 from mapzen/lua

Lua
Merge remote-tracking branch 'origin/master' into dwn
Ready to test the A* algorithm at its simplest form!
Benchmark for adjacency list