Reformatted data successfully

 - All arrays now contained within a single array of cells
House Keeping -> Added comments for solver functions
Added Particle System though not interpolating yet
Particle System now interpolating from velocity field...

 - Particles now bilinearly interpolating from grid input
 - Previously boundary condition fixed

NB: Merged to master and had forgot to commit… Doh! Though luckily
managed to rewrite all code in an hour.. Phew!