delete a dead variable

Dependencies

• [2] QFFTXR7E new file-system format for freewheeling apps
• [3] TNRO6KLZ new live app

Change contents

• replacement in main.lua at line 96
  [2.1481]→[2.1481:1503](∅→∅)
  − app.load_all(files)
  [2.1481]

  [3.3719]
  + app.load_all()