Review `manager` and split responsibilities

[cschreib]

Identified categories:

• [x] input

  • input_manager: manage input state and events
  • modal frame moving and resizing
  • hovered frame
  • key bindings --> to keybinder
  • set_key_binding --> to keybinder
  • remove_key_binding --> to keybinder
  • start_moving
  • stop_moving
  • is_moving
  • start_sizing
  • stop_sizing
  • is_sizing
  • get_movement
  • notify_object_moved
  • enable_input
  • toggle_input
  • is_input_enabled
  • get_hovered_frame
  • notify_hovered_frame_dirty
  • request_focus

• [x] sol::state + ...:

  • own and give access to lua state
  • get_lua
  • create_lua --> renamed to register_lua_glues and hide lua creation

• [x] addon_parser:

  • contains list of addons
  • parse folders for layouts and script files
  • add_addon_directory --> left in manager
  • clear_addon_directory_list --> left in manager
  • get_current_addon
  • set_current_addon
  • parse_file_name --> moved to uiobject

• [x] misc (what to do about these?):

  • interface scaling factor
  • set_interface_scaling_factor --> keep
  • get_interface_scaling_factor --> keep
  • print_statistics --> removed
  • print_ui --> keep
  • load_ui --> keep
  • close_ui --> keep
  • reload_ui --> keep
  • reload_ui_now --> keep
  • is_loading_ui --> removed
  • is_loaded --> keep
  • update --> keep
  • on_event --> keep

• [x] uiobject_factory:

  • frame/region factory functions
  • create_uiobject
  • create_frame
  • create_layered_region
  • register_frame_type
  • register_region_type

• [x] virtual_object_registry:

  • contains & owns virtual frames
  • create_virtual_root_frame
  • get_virtual_uiobject_list

• [x] frame_container:

  • contains & owns root frames
  • create_root_frame
  • add_root_frame
  • remove_root_frame
  • get_root_frames

• [x] uiroot:

  • frame_renderer: contains strata for all frames
  • frame_container: contains & owns root frames
  • contains & owns root frames
  • render_ui
  • enable_caching
  • toggle_caching
  • is_caching_enabled
  • get_highest_level --> moved to frame_renderer
  • get_target_dimensions
  • begin --> removed
  • end --> removed

• [x] localizer:

  • translations of text and locale

• [x] renderer:

  • implements low level vertex rendering

• [x] event_manager:

  • generate events and contains event receivers

• [x] uiobject_registry:

  • contains all uiobjects
  • query object by name
  • check valid name
  • check_uiobject_name
  • add_uiobject
  • remove_uiobject
  • remove_frame
  • get_uiobject_by_name