FMpiFmaDivider: This class is meant to split an FMA file into balanced
  smaller sub-files. Each sub-file is a stand-alone FMA file of its own
  that can be loaded with the FFmaGenericLoader. A main sub-file is also
  created. It can be used to retrive the total number of particles among
  the files.

testFMpiFmaDivider: renamed from testFMPIParticleDivider