clear error message on unknown definition

Dependencies

• [2] 5U3UBEQD new command: batch GET
• [3] BSDXVB3H backport some doc updates and renames
• [4] LRDM35CE app running again
• [5] QFURHRTP rename globals to have a single uppercase letter

Change contents

• replacement in live.lua at line 239
  [3.7050]→[3.764:815](∅→∅)
  − live.send_to_driver(live.get_binding(binding))
  [3.7050]

  [2.8]
  + local val = live.get_binding(binding)

  + if val then

  + live.send_to_driver(val)

  + else

  + live.send_to_driver('ERROR no such value')

  + end