Adds transformation functions stub

Added stub for all transformations functions supported on
ModSecurity 2.9

src/actions/transformations/base64_decode_ext.h

@@ -0,0 +1,44 @@
+/**
+ * ModSecurity, http://www.modsecurity.org/
+ * Copyright (c) 2015 Trustwave Holdings, Inc. (http://www.trustwave.com/)
+ *
+ * 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
+ *
+ * If any of the files related to licensing are missing or if you have any
+ * other questions related to licensing please contact Trustwave Holdings, Inc.
+ * directly using the email address security@modsecurity.org.
+ *
+ */
+
+#include <string>
+
+#include "actions/action.h"
+#include "actions/transformations/transformation.h"
+
+#ifndef SRC_ACTIONS_TRANSFORMATIONS_BASE64_DECODE_EXT_H_
+#define SRC_ACTIONS_TRANSFORMATIONS_BASE64_DECODE_EXT_H_
+
+#ifdef __cplusplus
+namespace ModSecurity {
+class Assay;
+
+namespace actions {
+namespace transformations {
+
+class Base64DecodeExt : public Transformation {
+ public:
+    explicit Base64DecodeExt(std::string action);
+    std::string& evaluate(std::string exp,
+        Assay *assay) override;
+};
+
+}  // namespace transformations
+}  // namespace actions
+}  // namespace ModSecurity
+
+#endif
+
+#endif  // SRC_ACTIONS_TRANSFORMATIONS_BASE64_DECODE_EXT_H_