Version 1.0:
	first release...

Version 1.1:
	coordinatete plane class separated

Version 1.2:
	class names changed
	interface improved

Version 1.3:
	text labels added
	gl2ps library included in distribution
	htl-1.3 support implemented
	htlplot viewer added

Version 1.4:
	some bugs fixed
	graphical interface improved
	examples separated to demo dir

Version 1.5:
	OpenGL-code improved

Version 1.6:
	scaling/movement interface improved
	labels improved
	menus improved
	gl2ps library updated to version 1.1.2
	textured background added
	getopt included in distribution

Version 1.7: skiped

Version 1.8:
        unnecessary stuff exluded from distribution
	gl2ps library updated to version 1.2.2

