Improve docs for Thread
Improve docs for Thread

An attempt to improve the documentation for Thread
- Adds documentation on how and when the `wait_to_finish` should be used
- Adds a note on what to be careful about when using `wait_to_finish`
vkbsb/godot,sanikoyes/godot,Zylann/godot,BastiaanOlij/godot,vnen/godot,Zylann/godot,ZuBsPaCe/godot,BastiaanOlij/godot,Valentactive/godot,Valentactive/godot,DmitriySalnikov/godot,Zylann/godot,josempans/godot,godotengine/godot,godotengine/godot,akien-mga/godot,sanikoyes/godot,guilhermefelipecgs/godot,josempans/godot,guilhermefelipecgs/godot,akien-mga/godot,josempans/godot,firefly2442/godot,ZuBsPaCe/godot,vnen/godot,pkowal1982/godot,sanikoyes/godot,Shockblast/godot,vkbsb/godot,firefly2442/godot,Valentactive/godot,firefly2442/godot,DmitriySalnikov/godot,vnen/godot,Faless/godot,DmitriySalnikov/godot,akien-mga/godot,Shockblast/godot,vkbsb/godot,Faless/godot,ZuBsPaCe/godot,Faless/godot,firefly2442/godot,Valentactive/godot,BastiaanOlij/godot,godotengine/godot,BastiaanOlij/godot,sanikoyes/godot,Valentactive/godot,ZuBsPaCe/godot,Faless/godot,akien-mga/godot,DmitriySalnikov/godot,vkbsb/godot,godotengine/godot,Faless/godot,josempans/godot,Shockblast/godot,josempans/godot,akien-mga/godot,Faless/godot,Faless/godot,guilhermefelipecgs/godot,godotengine/godot,vkbsb/godot,Valentactive/godot,akien-mga/godot,firefly2442/godot,godotengine/godot,BastiaanOlij/godot,vnen/godot,guilhermefelipecgs/godot,pkowal1982/godot,pkowal1982/godot,Zylann/godot,BastiaanOlij/godot,firefly2442/godot,guilhermefelipecgs/godot,vkbsb/godot,ZuBsPaCe/godot,vnen/godot,vnen/godot,guilhermefelipecgs/godot,pkowal1982/godot,guilhermefelipecgs/godot,akien-mga/godot,Zylann/godot,josempans/godot,josempans/godot,akien-mga/godot,Zylann/godot,Shockblast/godot,vnen/godot,godotengine/godot,BastiaanOlij/godot,Faless/godot,sanikoyes/godot,ZuBsPaCe/godot,Shockblast/godot,vkbsb/godot,Valentactive/godot,firefly2442/godot,sanikoyes/godot,pkowal1982/godot,DmitriySalnikov/godot,vnen/godot,DmitriySalnikov/godot,DmitriySalnikov/godot,sanikoyes/godot,godotengine/godot,josempans/godot,firefly2442/godot,Valentactive/godot,pkowal1982/godot,Zylann/godot,Shockblast/godot,Shockblast/godot,Shockblast/godot,ZuBsPaCe/godot,vkbsb/godot,sanikoyes/godot,guilhermefelipecgs/godot,ZuBsPaCe/godot,pkowal1982/godot,BastiaanOlij/godot,pkowal1982/godot,Zylann/godot