readme: represent recent API changes in Readme
readme: represent recent API changes in Readme

dbralir/glad,bsmr-opengl/glad,0x1100/glad,hrehfeld/glad,valeriog-crytek/glad,aaronmjacobs/glad,hrehfeld/glad,aaronmjacobs/glad,QUSpilPrgm/glad,dbralir/glad,valeriog-crytek/glad,hrehfeld/glad,0x1100/glad,0x1100/glad,0x1100/glad,QUSpilPrgm/glad,QUSpilPrgm/glad,hrehfeld/glad,aaronmjacobs/glad,QUSpilPrgm/glad,dbralir/glad,valeriog-crytek/glad,bsmr-opengl/glad,dbralir/glad,bsmr-opengl/glad,bsmr-opengl/glad,valeriog-crytek/glad,aaronmjacobs/glad