Wayland support

Based on the original port to Wayland by: Joel Teichroeb, Benjamin Franzke, Scott Moreau, et al.

Additional changes in this commit, done by me:

* Wayland uses the common EGL framework
* EGL can now create a desktop OpenGL context
* testgl2 loads GL functions dynamically, no need to link to libGL anymore
* Assorted fixes to the Wayland backend

Tested on the Weston Compositor (v1.0.5) that ships with Ubuntu 13.10,
running Weston under X. Tests ran: testrendercopyex (all backends), testgl2, testgles2,testintersections

test/Makefile.in

@@ -128,13 +128,13 @@ testgesture$(EXE): $(srcdir)/testgesture.c
 	$(CC) -o $@ $^ $(CFLAGS) $(LIBS) @MATHLIB@
  
 testgl2$(EXE): $(srcdir)/testgl2.c
-	$(CC) -o $@ $^ $(CFLAGS) $(LIBS) @GLLIB@ @MATHLIB@
+	$(CC) -o $@ $^ $(CFLAGS) $(LIBS) @MATHLIB@
 
 testgles$(EXE): $(srcdir)/testgles.c
 	$(CC) -o $@ $^ $(CFLAGS) $(LIBS) @GLESLIB@ @MATHLIB@
 
 testgles2$(EXE): $(srcdir)/testgles2.c
-	$(CC) -o $@ $^ $(CFLAGS) $(LIBS) @GLES2LIB@ @MATHLIB@
+	$(CC) -o $@ $^ $(CFLAGS) $(LIBS) @MATHLIB@
 
 testhaptic$(EXE): $(srcdir)/testhaptic.c
 	$(CC) -o $@ $^ $(CFLAGS) $(LIBS)