fix cmake and update sc

[dyfer]

I've updated SC sources and made changes to CMake to make SuperColliderAU build. Fixes #4, and #7, supersedes #8.

Aside from CMake updates, I made one change to the source, that fixed the error from auval:

Test MIDI
ERROR: -4 IN CALL MusicDeviceMIDIEvent

auval now passes, but only for no more than two runs of the plugin (-r 2). I'd like to file this as a separate issue later.

[g-roma]

Thanks for the fixes! I am now on an up to date OS which should make it easier for me to maintain SCAU.
Building and running is working for me on Catalina + Reaper with these changes at the moment. However I am seeing a segmentation fault in auval at the end, wich seems to point to something trickier. Are you not seeing it?
I'd be inclined to merge this regardless, as the update is long due, but this seems something that will need fixing as well.

[dyfer]

Thanks @g-roma !
Yes, I was seeing segfault in auval, but only when -r parameter was 3 and up, that's why I temporarily lowered it.
For me it seemed to happen on the third start of the plugin somewhere after this line (thanks for leaving the debug printing in!) I'd treat it as a separate issue, unless you have an idea why it is happening, then I'd be happy to include a fix for it.

[g-roma]

Looks good although it crashes at auval exit even with one go in my machine at the moment (working on a fix). Seems to work in AU host anyway.