remove superfluous stuff.
* arp
* dhcpc
* mdns-sd
* sntp
* ptp
* tuio1
* scsynth
* dummy
* custom
* ipv4ll
add missing break in switch statement.
fix compilation with gcc-11.
update build status link in REAME.
prototype gitlab ci recipe.
fix sensor number range in OSC API.
get rid of INFINITY min/max ranges in OSC API.
set default MIDI controller to SC1 (0x46) for MPE.
dump firmware version in releasor.
support 'b'lob type output for oscmidi engine.
imporove SLIP encoding.
* do double SLIP encoding according to OSC-1.1 spec.
* use short-cut for more efficient encoding.
implement MIDI MPE mode in oscmidi engine.