Add back codec.

Need to figure out why this isn't loading correctly at run time. Refs #1

grails-app/utils/com/megatome/grails/util/URLSafeBase64Codec.groovy

@@ -0,0 +1,31 @@
+package com.megatome.grails.util
+
+/**
+ * Copyright 2010-2015 Megatome Technologies
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+class URLSafeBase64Codec {
+    /**
+     * Simple encoding required by the Mailhide API to make the Base64 string URL safe
+     */
+    static encode = { target ->
+        if (target == null) {
+            return target
+        }
+
+        String firstPass = target.encodeAsBase64()
+        firstPass.replaceAll("\\+", "-").replaceAll("/", "_")
+    }
+}