Warnings improvements

* Turn off global-constructors warning. These are needed to implement cRoot signal handler functionality
* Add Clang flags based on version lookup instead of a compile test. The CMake config process is single threaded and slow enough already
* Reduced GetStackValue verbosity
+ Clarify EnchantmentLevel, StayCount, AlwaysTicked, ViewDistance signedness
+ Give SettingsRepositoryInterface a move constructor to simplify main.cpp code
- Remove do {} while (false) construction in redstone handler

src/Bindings/ManualBindings.cpp

@@ -2760,7 +2760,7 @@ static int tolua_cItem_EnchantByXPLevels(lua_State * tolua_S)
 
 	// Get the params:
 	cItem * Self;
-	int NumXPLevels;
+	unsigned NumXPLevels;
 	L.GetStackValue(1, Self);
 	L.GetStackValue(2, NumXPLevels);