a new event: receiving code changes from the driver

Dependencies

• [2] 5OVKHVY6 nice way to make on.* handlers more discoverable
• [*] LRDM35CE app running again

Change contents

• edit in live.lua at line 151
  [4.5013]

  [4.5013]
  + if on.code_changed then on.code_changed() end
• edit in 0001-on at line 7
  [2.247]

  [2.247]
  + -- on.code_changed (runs after every time the driver sends a new definition)