change class names

[yomichi]

Two types of name conventions of classes appear: snake_case and CamelCase.
This PR chooses CamelCase because PEP8 recommends it.
While abICS v2, we also offer the old names as aliases for the backward compatibility.

• abics.mc
  • model -> Model
  • observer_base -> ObserverBase
  • grid_1D -> Grid1D
• abics.applications.latgas_abinitio_interface.default_observer
  • default_observer -> DefaultObserver
  • ensemble_error_observer -> EnsembleErrorObserver
• abics.applications.latgas_abinitio_interface.model_setup
  • dft_latgas -> DFTLatticeGas
  • energy_lst -> EnergyList
  • group -> Group
  • defect_sublattice -> DefectSublattice
  • config -> Config
• abics.applications.latgas_abinitio_interface.run_base_mpi
  • runner -> Runner
  • runner_multistep -> RunnerMultistep
  • runner_ensemble -> RunnerEnsemble
  • run_mpispawn -> RunMpispawn
  • run_mpispawn_ready -> RunMpispawnReady
  • run_mpispawn_wrapper -> RunMpispawnWrapper
  • run_subprocess -> RunSubprocess
  • run_function -> RunFunction