Added options to render diagrams using plantuml and mermaidjs external tools

src/util/util.h

@@ -98,6 +98,13 @@ std::string trim_typename(const std::string &s);
  */
 std::string get_process_output(const std::string &command);
 
+/**
+ * @brief Execute command shell and throw exception if command fails
+ *
+ * @param command Command to execute
+ */
+void check_process_output(const std::string &command);
+
 /**
  * @brief Get value of an environment variable
  *