Situation: an element is mentioned in page_layout (as autogenerated element), but missing in elements.yml.
When I try to create that page it throws:
+++++++++ Error: undefined method `except' for nil:NilClass +++++++++++++
Especially for designers working with alchemy it would be great to have something like "Element missing in elements.yml, please create it first".
Displaying a error message if the element name could not be found in …
…elements.yml. Closes #225