Added SDL2 support.
Added SDL2 support.

jdryg/bgfx,sergeScherbakov/bgfx,marco-we/bgfx,ktotheoz/bgfx,LSBOSS/bgfx,bkaradzic/bgfx,BlueCrystalLabs/bgfx,Extrawurst/bgfx,mendsley/bgfx,cyndis/bgfx,Synxis/bgfx,attilaz/bgfx,emoon/bgfx,ocornut/bgfx,Vertexwahn/bgfx,ming4883/bgfx,janstk/bgfx,elmindreda/bgfx,ocornut/bgfx,kondrak/bgfx,janstk/bgfx,fluffyfreak/bgfx,mcanthony/bgfx,cuavas/bgfx,ktotheoz/bgfx,0-wiz-0/bgfx,bkaradzic/bgfx,Extrawurst/bgfx,Extrawurst/bgfx,v3n/bgfx,janstk/bgfx,emoon/bgfx,mendsley/bgfx,ming4883/bgfx,aonorin/bgfx,andr3wmac/bgfx,darkimage/bgfx,septag/bgfx,jdryg/bgfx,ming4883/bgfx,BlueCrystalLabs/bgfx,bkaradzic/bgfx,marco-we/bgfx,mendsley/bgfx,Synxis/bgfx,ktotheoz/bgfx,Vertexwahn/bgfx,andr3wmac/bgfx,jpcy/bgfx,andr3wmac/bgfx,v3n/bgfx,jpcy/bgfx,v3n/bgfx,cyndis/bgfx,LWJGL-CI/bgfx,0-wiz-0/bgfx,septag/bgfx,darkimage/bgfx,LWJGL-CI/bgfx,LSBOSS/bgfx,jdryg/bgfx,LSBOSS/bgfx,marco-we/bgfx,sergeScherbakov/bgfx,jpcy/bgfx,BlueCrystalLabs/bgfx,kondrak/bgfx,fluffyfreak/bgfx,MikePopoloski/bgfx,Synxis/bgfx,mcanthony/bgfx,jdryg/bgfx,MikePopoloski/bgfx,aonorin/bgfx,LWJGL-CI/bgfx,elmindreda/bgfx,aonorin/bgfx,ocornut/bgfx,attilaz/bgfx,LWJGL-CI/bgfx,kondrak/bgfx,cyndis/bgfx,jpcy/bgfx,MikePopoloski/bgfx,darkimage/bgfx,sergeScherbakov/bgfx,Vertexwahn/bgfx,mmicko/bgfx,septag/bgfx,elmindreda/bgfx,cuavas/bgfx,bkaradzic/bgfx,mcanthony/bgfx,mmicko/bgfx,fluffyfreak/bgfx,0-wiz-0/bgfx,emoon/bgfx,mmicko/bgfx,fluffyfreak/bgfx,cuavas/bgfx,attilaz/bgfx