Remove calls to other plugin
Remove calls to other plugin

Plugins cannot call other plugin API, removing for now.

Change-Id: I93e4e7c5ebf898a8264cbc66cbc30c3758cbab61

OpenChemistry/avogadrolibs,ghutchis/avogadrolibs,OpenChemistry/avogadrolibs,OpenChemistry/avogadrolibs,ghutchis/avogadrolibs,OpenChemistry/avogadrolibs,ghutchis/avogadrolibs,ghutchis/avogadrolibs,ghutchis/avogadrolibs,OpenChemistry/avogadrolibs