bugfix for non-ASCII

Dependencies

• [2] 2RXZ3PGO beginning of a new approach to scroll+wrap
• [3] WY3JD6W6 bugfix
• [4] XNFTJHC4 split keyboard handling between Text and Drawing
• [*] BULPIBEG beginnings of a module for the text editor
• [*] 2ZYV7D3W handle tab characters

Change contents

• edit in text.lua at line 885
  [7.99]

  [3.171]
  + if Selection1.line then Text.delete_selection() end
• replacement in text.lua at line 888
  [2.485]→[2.485:556](∅→∅)
  − byte_offset = utf8.offset(Lines[Cursor1.line].data, Cursor1.pos-1)
  [2.485]

  [3.285]
  + byte_offset = utf8.offset(Lines[Cursor1.line].data, Cursor1.pos)
• replacement in text.lua at line 890
  [3.292]→[3.292:312](∅→∅)
  − byte_offset = 0
  [3.292]

  [3.312]
  + byte_offset = 1
• replacement in text.lua at line 892
  [3.318]→[2.557:695](∅→∅)
  − Lines[Cursor1.line].data = string.sub(Lines[Cursor1.line].data, 1, byte_offset)..t..string.sub(Lines[Cursor1.line].data, byte_offset+1)
  [3.318]

  [2.695]
  + Lines[Cursor1.line].data = string.sub(Lines[Cursor1.line].data, 1, byte_offset-1)..t..string.sub(Lines[Cursor1.line].data, byte_offset)