Merge branch 'fix-readme-rendering' into 'develop'

Fix readme rendering

See merge request !81

data_repo_renderer/__init__.py

@@ -488,6 +488,8 @@ class ReadmeRenderer(Renderer):
         yaml_dict = self._maybe_include_credentials(yaml_dict)
         yaml_dict = self._maybe_include_acknowledgements(yaml_dict)
         yaml_dict = self._maybe_include_citations(yaml_dict)
+        if "known_issues" not in yaml_dict:
+            yaml_dict["known_issues"] = ""
 
         super(ReadmeRenderer, self).__init__(yaml_dict=yaml_dict, *args,
                                              **kwargs)