Changed sysex handling

Instead of creating sysex MIDI file in each time,
added sysex directory and three MIDI files.

As a result, we can now use any MIDI files for sysex reset
without fixing source code.
Changed timing of sysex playback, and modified sysex files

Now sysex played at following timings:
* at the first of each midi file
* when "stop" button is clicked
* after xpmidi+ is started

Following above changes, added "Note off" messages for all channels to
sysex files
Deleted "KillOnAbort" option

I could not imagine the situation which needs "KillOnAbort" option...
Renamed script file
Merge branch 'dev'