cleanup particleToGrid

- rename energyDensity to CompuerGridValuePerFrame
- rename ComputeEnergyDensityOptions to ComputeGridValueOptions
rename particleToGrid usage in unitless

- use ComputeGridValuePerFrame in fileOutput.unitless
- delete inot needed inlcude of particleToGrid classes in HDF5Writer and AdiosWriter
Merge pull request #329 from psychocoderHPC/cleanup-particleToGrid

Cleanup particleToGrid class