func AttachShader(p Program, s Shader) {
	gl.AttachShader(p.Value, s.Value)
}
AttachShader attaches a shader to a program.

http://www.khronos.org/opengles/sdk/docs/man3/html/glAttachShader.xhtml
package gl
import (
	"log"
	"strings"
	"unsafe"
	"github.com/go-gl/gl/v2.1/gl"
)
var ContextWatcher = new(contextWatcher)
type contextWatcher struct {
	initGL bool
}
func (cw *contextWatcher) OnMakeCurrent(context interface{}) {
	if !cw.initGL {
		err := gl.Init()
		if err != nil {
			log.Fatalln("gl.Init:", err)
		}
		cw.initGL = true
	}
}
func (contextWatcher) OnDetach() {}
func ActiveTexture(texture Enum) {
	gl.ActiveTexture(uint32(texture))
}