implement basic Lattice constructor, dirToSteps function
Properly calculate & store neighbor poiners
Properly calculate & store neighbor poiners
Merge branch 'lattice_rewrite' of github.com:cglosser/Lattice-Boltzmann into lattice_rewrite

Conflicts:
	src/driver.cpp
Implement streaming update step
Change Lattice constructor to use init lists (const values)
full documentation
implement collision step
implement collision step

Second working version with reference neighbors!
Merge branch 'lattice_rewrite' of github.com:cglosser/Lattice-Boltzmann into lattice_rewrite
Refactor direction code for easy reversals
Merge branch 'headmerge' into lattice_rewrite