Fixed drawText() to handle NULL or empty string.
Fixed drawText() to handle NULL or empty string.

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