Added documentation for the OS class MIDI functions.
Added documentation for the OS class MIDI functions.

pkowal1982/godot,vnen/godot,ex/godot,Paulloz/godot,sanikoyes/godot,BastiaanOlij/godot,honix/godot,Zylann/godot,josempans/godot,MarianoGnu/godot,DmitriySalnikov/godot,guilhermefelipecgs/godot,vnen/godot,godotengine/godot,sanikoyes/godot,DmitriySalnikov/godot,DmitriySalnikov/godot,josempans/godot,BastiaanOlij/godot,vkbsb/godot,pkowal1982/godot,Valentactive/godot,sanikoyes/godot,Shockblast/godot,honix/godot,ex/godot,ex/godot,Faless/godot,godotengine/godot,Zylann/godot,akien-mga/godot,Shockblast/godot,pkowal1982/godot,DmitriySalnikov/godot,Valentactive/godot,godotengine/godot,firefly2442/godot,Shockblast/godot,firefly2442/godot,josempans/godot,firefly2442/godot,ZuBsPaCe/godot,guilhermefelipecgs/godot,MarianoGnu/godot,sanikoyes/godot,akien-mga/godot,Faless/godot,sanikoyes/godot,sanikoyes/godot,Shockblast/godot,pkowal1982/godot,guilhermefelipecgs/godot,pkowal1982/godot,guilhermefelipecgs/godot,Valentactive/godot,akien-mga/godot,josempans/godot,ex/godot,Faless/godot,Zylann/godot,BastiaanOlij/godot,Valentactive/godot,Shockblast/godot,josempans/godot,vnen/godot,akien-mga/godot,DmitriySalnikov/godot,Zylann/godot,vkbsb/godot,firefly2442/godot,ZuBsPaCe/godot,ZuBsPaCe/godot,Paulloz/godot,akien-mga/godot,Paulloz/godot,Valentactive/godot,MarianoGnu/godot,Paulloz/godot,honix/godot,MarianoGnu/godot,MarianoGnu/godot,Paulloz/godot,Paulloz/godot,vkbsb/godot,firefly2442/godot,DmitriySalnikov/godot,BastiaanOlij/godot,pkowal1982/godot,Shockblast/godot,honix/godot,ex/godot,vnen/godot,godotengine/godot,godotengine/godot,ZuBsPaCe/godot,vnen/godot,pkowal1982/godot,vkbsb/godot,vnen/godot,godotengine/godot,vkbsb/godot,godotengine/godot,guilhermefelipecgs/godot,akien-mga/godot,ZuBsPaCe/godot,honix/godot,BastiaanOlij/godot,vkbsb/godot,MarianoGnu/godot,firefly2442/godot,DmitriySalnikov/godot,akien-mga/godot,BastiaanOlij/godot,godotengine/godot,guilhermefelipecgs/godot,MarianoGnu/godot,guilhermefelipecgs/godot,Faless/godot,akien-mga/godot,vkbsb/godot,pkowal1982/godot,honix/godot,josempans/godot,guilhermefelipecgs/godot,MarianoGnu/godot,sanikoyes/godot,Zylann/godot,vnen/godot,vnen/godot,BastiaanOlij/godot,Faless/godot,Valentactive/godot,ZuBsPaCe/godot,vkbsb/godot,ex/godot,Zylann/godot,firefly2442/godot,sanikoyes/godot,Valentactive/godot,josempans/godot,Zylann/godot,josempans/godot,ZuBsPaCe/godot,Shockblast/godot,Paulloz/godot,Faless/godot,Faless/godot,ex/godot,Valentactive/godot,Shockblast/godot,ZuBsPaCe/godot,ex/godot,Faless/godot,Zylann/godot,firefly2442/godot,BastiaanOlij/godot