Document screen_reset.
Document escaped.
Document keyscan_all.
Document do_we_have_required_objects_for_escape,
Document screenlocstring_plot.
Document some common assembly language patterns used in this code.
Add an enum for 'no message'.
Rename do_we_have_required_objects_for_escape -> have_required_items, do_we_have_objects -> item_to_bitmask.
Document map shunting routines.