Expanded path functions tests
Expanded path functions tests

The new tests cover:
- A file with empty extension.
- A file with only extension (a "hidden" file, unix style).
- A file directly at the windows top level directory.
- A file directly at the unix root directory.
- A file directly at the res:// base directory.
godotengine/godot,BastiaanOlij/godot,ZuBsPaCe/godot,Shockblast/godot,Zylann/godot,akien-mga/godot,Zylann/godot,Faless/godot,firefly2442/godot,Valentactive/godot,Faless/godot,vkbsb/godot,vkbsb/godot,vnen/godot,akien-mga/godot,Valentactive/godot,sanikoyes/godot,Zylann/godot,BastiaanOlij/godot,guilhermefelipecgs/godot,firefly2442/godot,firefly2442/godot,Zylann/godot,BastiaanOlij/godot,godotengine/godot,firefly2442/godot,Faless/godot,BastiaanOlij/godot,pkowal1982/godot,sanikoyes/godot,josempans/godot,Valentactive/godot,DmitriySalnikov/godot,Valentactive/godot,josempans/godot,sanikoyes/godot,josempans/godot,guilhermefelipecgs/godot,ZuBsPaCe/godot,vnen/godot,Shockblast/godot,vnen/godot,DmitriySalnikov/godot,vkbsb/godot,guilhermefelipecgs/godot,BastiaanOlij/godot,godotengine/godot,Shockblast/godot,Valentactive/godot,akien-mga/godot,Shockblast/godot,vnen/godot,Zylann/godot,sanikoyes/godot,Shockblast/godot,DmitriySalnikov/godot,Faless/godot,vkbsb/godot,guilhermefelipecgs/godot,godotengine/godot,BastiaanOlij/godot,ZuBsPaCe/godot,akien-mga/godot,sanikoyes/godot,guilhermefelipecgs/godot,pkowal1982/godot,guilhermefelipecgs/godot,pkowal1982/godot,josempans/godot,godotengine/godot,BastiaanOlij/godot,josempans/godot,ZuBsPaCe/godot,akien-mga/godot,pkowal1982/godot,Zylann/godot,firefly2442/godot,pkowal1982/godot,vnen/godot,Faless/godot,sanikoyes/godot,Valentactive/godot,Faless/godot,Zylann/godot,vkbsb/godot,vnen/godot,pkowal1982/godot,firefly2442/godot,godotengine/godot,vkbsb/godot,josempans/godot,vnen/godot,godotengine/godot,Valentactive/godot,ZuBsPaCe/godot,josempans/godot,Shockblast/godot,DmitriySalnikov/godot,DmitriySalnikov/godot,Zylann/godot,guilhermefelipecgs/godot,akien-mga/godot,akien-mga/godot,guilhermefelipecgs/godot,Shockblast/godot,Shockblast/godot,Faless/godot,pkowal1982/godot,vkbsb/godot,sanikoyes/godot,Valentactive/godot,vnen/godot,josempans/godot,firefly2442/godot,akien-mga/godot,vkbsb/godot,Faless/godot,sanikoyes/godot,DmitriySalnikov/godot,BastiaanOlij/godot,ZuBsPaCe/godot,ZuBsPaCe/godot,godotengine/godot,DmitriySalnikov/godot,pkowal1982/godot,ZuBsPaCe/godot,firefly2442/godot