Implement domain actions (fill, set, remove)

[BryanRumsey]

• The domain needs a data structure to store actions and preserve the order of application.
• also needs functions to add new actions.
  • add_fill_action
  • add_set_action
  • add_remove_action
• Refactor the following functions to use the above functions
  • fill_with_particles should use add_fill_action
  • set_properties should use add_set_action