Indented and added randomUniform and randomGaussian in vec3.cpp.
Changed so resetVelocityMaxwellian uses randomGaussian in vec3.cpp.
Saving atom positions in Angstroms instead of atomic units.
Indentation.
Added 100 atoms uniformly, randomly placed as an example. Fixed
timestep. Added unitConverter example usage also to show what the units
of length, velocity, time and mass are.