Add missing documentation in vertex buffer
Add missing documentation in vertex buffer

carbidegames/glium,bvssvni/glium,rozaliev/glium,sdotz/glium,nicokoch/glium,msiglreith/glium,caldwell/glium,cpjreynolds/glium,acolley/glium,glium/glium,christopheraugustus/glium,tomaka/glium,binsoftware/glium,TyOverby/glium