add != color op + tests, fixes leafo#79

Author: leafo

scss.inc.php

@@ -1029,6 +1029,8 @@ protected function op_color_color($op, $left, $right) {
 				break;
 			case "==":
 				return $this->op_eq($left, $right);
+			case "!=":
+				return $this->op_neq($left, $right);
 			default:
 				$this->throwError("color: unknown op $op");
 			}

tests/inputs/operators.scss

@@ -47,6 +47,12 @@ div {
     color: rgba(1,2,3, 0.5) - 2;
 
     color: blue + 34;
+
+    color: #fff == #000;
+    color: #fff == #fff;
+
+    color: #fff != #000;
+    color: #fff != #fff;
 }