Build System Changes

-=-=-=-=-=-=-=-=-=-=

Build System:
-Big clean up of SCons, changed how builds are done to a much cleaner method (check the Github Wiki for instructions).
-Deactivated BlackBerry10 (sorry), if no mantainer found (or BlackBerry does not send us a Passort ;), platform will be removed as we have no longer devices to test.

Engine:
-Removed deprecated object and scene format (was in there just for compatibility, not in use since a long time).
-Added ability to open scenes even if a node type was removed (will try to guess the closest type).
-Removed deprecated node types.

modules/gdscript/gd_script.cpp

@@ -2410,7 +2410,6 @@ void GDScriptLanguage::get_reserved_words(List<String> *p_words) const  {
 		"func"	,
 		"if"	,
 		"in"	,
-		"varl",
 		"null"	,
 		"return"	,
 		"self"	,