Bodged in support for region pragmas

Have them as basic directives

They're similar to the assert and panic macros but are hardcoded to true

#region    (<string literal>)
#endregion (<string literal>)

src/parser.cpp

@@ -5147,7 +5147,7 @@ gb_internal Ast *parse_stmt(AstFile *f) {
 				break;
 			}
 			return s;
-		} else if (tag == "assert" || tag == "panic") {
+		} else if (tag == "assert" || tag == "panic" || tag == "region" || tag == "endregion") {
 			Ast *t = ast_basic_directive(f, hash_token, name);
 			Ast *stmt = ast_expr_stmt(f, parse_call_expr(f, t));
 			expect_semicolon(f);