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Littles changes
add clap-plugin-helper.h, which simplify the plugin creation
Update the midi parser
Split plugin's functionality into extensions.
Remove feedback loop.
plugin->process() returns a status
Moving unrequired bits from plugin to extension
Update thyns to match the current headers
Remove attr has_gui, as gui is now an extension, and add attr remote_processing
Update documentation
Fix compil
Started a jack host
Synthesizer + jack host works!!!
Remove NOTE_MODULATION
Tentative to bootstrap static qt build
Update qt build config
Reduce qt build
Disable qt-script