First working version of Mermaid class diagram generator

src/common/types.h

@@ -37,7 +37,7 @@ using id_t = int64_t;
 enum class generator_type_t {
     plantuml, /*!< Diagrams will be gnerated in PlantUML format */
     json,     /*!< Diagrams will be generated in JSON format */
-    mermaid /*!< Diagrams will be generated in MermaidJS format */
+    mermaid   /*!< Diagrams will be generated in MermaidJS format */
 };
 
 std::string to_string(const std::string &s);