Remove call to obsolete debug function.
Add dirty implementation of lattice weights and bounced vectors.
Tweaks to timers.
New field initial condition initConst.
Add dirty advection / collision code.

Advection seems to work, collision maybe not?
Add MPI_Allreduce header.
Add mass / density functions.
Some cleanup.
Improve velocity helper functions.
Fix Makefile.
Pass connectivity rather than velocities.
Ugly hacks for equilibrium distribution and momentum conservation.