Cycles: hook up the CMake build system.

New build instructions for Ubuntu Linux in the wiki:
http://wiki.blender.org/index.php/Dev:2.5/Source/Cycles

intern/cycles/app/cycles_test.cpp

@@ -185,7 +185,7 @@ static void options_parse(int argc, const char **argv)
 {
 	options.width= 1024;
 	options.height= 512;
-	options.filepath = path_get("../../../test/models/elephants.xml");
+	options.filepath = "";
 	options.session = NULL;
 	options.quiet = false;