renamed Pmoments as SpeciesMoms
renamed Imoments as MImoments
moved initialization code into main solver
renamed Solver.cpp MIsolver.cpp
moving code into solver class
syntax correction
replaced Field -> EMfields3D
removed Particles.h and typedef to Particles3Dcomm.h
more cleanup; renamed ipicblah.h to ipic_blah.h and eliminated some .h files