purge unused button infrastructure

Dependencies

• [2] K6DTOGOQ flip return value of button handlers
• [3] PP2IIHL6 stop putting button state in a global
• [4] LNUHQOGH start passing in Editor_state explicitly
• [5] 6D5MOJS4 allow buttons to interrupt events
• [6] ERQKFTPV extract method
• [7] 2L5MEZV3 experiment: new edit namespace
• [8] LF7BWEG4 group all editor globals
• [9] 4KC7I3E2 make colors easier to edit

Change contents

• edit in edit.lua at line 78
  [3.2727]→[3.15:44](∅→∅)
  − State.button_handlers = {}
• edit in edit.lua at line 130
  [3.4647]→[2.15:94](∅→∅),[2.94]→[3.172:254](∅→∅),[3.179]→[3.172:254](∅→∅),[3.172]→[3.172:254](∅→∅),[3.254]→[3.7016:7017](∅→∅),[3.7016]→[3.7016:7017](∅→∅)
  − if mouse_press_consumed_by_any_button_handler(State, x,y, mouse_button) then

  − -- press on a button and it returned 'true' to short-circuit

  − return

  − end

  −