Import aliases for Custom Classes

Import aliases support for Custom Classes. This allows you to import classes and other custom classes with an alias inside of a Custom Class.

This includes some improvements on "parseModuleDecl()"

hscript/Expr.hx

@@ -159,7 +159,7 @@ enum Error {
 
 enum ModuleDecl {
 	DPackage( path : Array<String> );
-	DImport( path : Array<String>, ?everything : Bool );
+	DImport( path : Array<String>, ?everything : Bool, ?asname:String );
 	DClass( c : ClassDecl );
 	DTypedef( c : TypeDecl );
 }