http: fix response headers and status code; clean up ft and gg

compiler/tests/mut_test.v

@@ -1,6 +1,19 @@
-fn test_mut() {
-	a := 1 
-	mut b := &a
-	*b = 10 
-	println(a) 
+fn foo(a mut []int) {
+	a[0] = 7 
+	a << 4 
+} 
+
+fn test_mut() {
+	mut a := [1,2,3] 
+	foo(mut a) 
+	assert a.len == 4 
+	assert a[0] == 7 
+	assert a[3] == 4 
+
+	n := 1 
+	mut b := &n 
+	*b = 10 
+
+	//mut b := mut a
+	//b = 10 
 }