* container_move is only called from the move command
* container_move_to was called from both the move command and the sticky
command, but the sticky command can easily not call it
* container_get_in_direction is only called from the focus command
Moving these functions to their respective commands gives better
separation of code and removes bloat from layout.c. These functions will
need to be refactored to take advantage of type safety, so separating
them will make this easier to refactor.
The following static functions have also been moved:
* is_parellel
* invert_movement
* move_offs
* container_limit
* workspace_rejigger
* move_out_of_tabs_stacks
* get_swayc_in_output_direction
They were all used by the move functions, except for the last one which
is used by focus.
Other changes:
* index_child has been renamed to container_sibling_index, moved to
container.c and made public
* sway_output_from_wlr has been renamed to output_from_wlr_output, moved
to output.c and made public
* container_handle_fullscreen_reparent has been made public
* sway_dir_to_wlr has been made public
No changes have been made to any of the moved functions, other than
updating calls to functions that have been renamed.
