GL capability: do depth comparisons and update the depth buffer

Foreign: GL_DEPTH_TEST

Property definitions

glesv2 $ GLCapabilities :: depth_test
	# GL capability: do depth comparisons and update the depth buffer
	#
	# Foreign: GL_DEPTH_TEST
	var depth_test: GLCap is lazy do return new GLCap(0x0B71)
lib/glesv2/glesv2.nit:1105,2--1108,58