Implement on_locc133 / on_hicc133 or create on_key new opcode

[kinwie]

These opcodes, on_locc133 on_hicc133 or start_locc133 start_hicc133
are listed already but not yet implemented in most sfz players.
CC133 is extended cc for keynumber.
The intention for its use is for triggering release samples that put on a key and triggered from another key.
In practical, it will be used for triggering cymbals release/choke/tail samples.

A short explanation for Drum kit mapping ;

1. Mapped for triggered by e-drum MIDI Controller. In this mapping mode, the function described above can be achieved by the use of on_locc130 on_hicc130. CC130 is polyphonic aftertouch. This is works and commonly supported by most e-drums.
2. Mapped for triggered by Keyboard MIDI Controller or by writing MIDI notes via host's pianoroll. In this mapping mode, the function described above not yet able to be achieved by the use of on_locc133 on_hicc133.

So, either implementing on_locc133 on_hicc133 and start_locc133 start_hicc133 OR made a new opcode : on_key which has the same function

[kinwie]

A description and test file for this case has been posted here :
https://github.com/kinwie/sfztest/wiki/Cymbal-choke-test-for-edrums-and-keyboard-mapping-mode
https://redtide.github.io/sfztest/Cymbal-choke-test-for-edrums-and-keyboard-mapping-mode/

[redtide]

or just on_cc as generic?