get rid of mm prefixes since the stuff lives in the mm namespace anyway

modules/mol/mm/examples/ethanol_example.py

modules/mol/mm/examples/ethanol_example_using_topology.py

modules/mol/mm/examples/gb_example.py

modules/mol/mm/examples/gb_example_traj.dcd

modules/mol/mm/examples/gb_example_traj.pdb

modules/mol/mm/examples/gb_example_writing_trajectory.py

modules/mol/mm/pymod/export_forcefield.cc

modules/mol/mm/pymod/export_interaction.cc

modules/mol/mm/pymod/export_modeller.cc

modules/mol/mm/pymod/export_observers.cc

modules/mol/mm/pymod/export_settings.cc

modules/mol/mm/pymod/export_simulation.cc

modules/mol/mm/pymod/wrap_mol_mm.cc

modules/mol/mm/src/CMakeLists.txt

modules/mol/mm/src/buildingblock.cc

modules/mol/mm/src/buildingblock.hh

modules/mol/mm/src/forcefield.cc

modules/mol/mm/src/forcefield.hh

modules/mol/mm/src/gromacs_block_modifiers.cc

modules/mol/mm/src/gromacs_block_modifiers.hh