-> UV Edge collapse

Added code to make 'Collapse Edges' handle UV's intelligently. This seems to work in just about every case that I can test, so it's turned on by default.

Also completely removed the 'collapse faces' command and code. I'm not sure what I was thinking with this in the first place since edge collapse does the same job while in in face mode. Because of this there is now just one single command that covers both situations called 'Collapse' which uses the edge collapse code.

source/blender/src/toolbox.c

@@ -940,7 +940,7 @@ static TBitem tb_mesh_edit_vertex[]= {
 
 static TBitem tb_mesh_edit_edge[]= {
 {	0, "Make Edge/Face|F", 			5, 		NULL},
-{	0, "Collapse Edges|Alt M", 14,			NULL},
+{	0, "Collapse|Alt M", 14,			NULL},
 {	0, "SEPR",						0, NULL},
 {	0, "Bevel|W, Alt 2", 					6, 		NULL},
 {	0, "Loop Subdivide|Ctrl R", 		4, 		NULL},
@@ -966,7 +966,6 @@ static TBitem tb_mesh_edit_face[]= {
 {	0, "Make Edge/Face|F", 			5, 		NULL},
 {	0, "Fill|Shift F", 				0, 		NULL},
 {	0, "Beautify Fill|Alt F", 			1, 		NULL},
-{	0, "Collapse Faces|Alt M",		8,		NULL},
 {	0, "SEPR",					0, NULL},
 {	0, "Convert to Triangles|Ctrl T", 	2, 		NULL},
 {	0, "Convert to Quads|Alt J", 		3, 		NULL},