Translation of the MIDI import panel
Fix #23521 : reading a workspace containing <file> tags crashes

The closing tag of the previous element was not read.
fix position of mmRest number
temporary fix for missing vtest files
Merge pull request #538 from mgavioli/Fix_23521_workspaces_wiith_images

Fix #23521 : reading a workspace containing <file> tags crashes
Merge pull request #529 from trig-ger/midi_tr

Translation of the MIDI import panel
 ChangeKeySig::flip() makes sure keymap gets updated
test for undo transpose
Merge pull request #540 from heuchi/23525_transpose_undo_keysig

23525 transpose undo keysig