Added some class methods to markdown renderer

Author: lainq

src/arguments/markdown.py

@@ -24,4 +24,15 @@ def print_mark_down_text(self):
         return rendered_markdown
 
     def __repr__(self):
-        return str(self.render)
+        return str(self.render)
+
+    def __len__(self):
+        if isinstance(self.render, str):
+            return len(self.render)
+        return -1
+
+    def __str__(self):
+        return str(self.render)
+
+    def __repr__(self):
+        return str(self.render)