A document may refer to a non a existing document

[benel]

Displaying a document that includes a non existing document results in the following exception being raised:

TypeError: null is not an object (evaluating 'x._id')

[benel]

Please note that this fix could be the first requirement to a feature that would pull the document from a different server (see #141).

[GwenRiou]

Created page for 404 error

[GwenRiou]

[benel]

@GwenRiou Thank you for your mockup.
I think however that the issue your project is interested in is #115 rather than this one.

This issue (138) relates with the case when the focused document does exist (in the center of the interface) and should be displayed but refers to a non-existing document (in the left margin).

[benel]

Recent refactoring changed the exception into an invalid displayed page.
This bug has been experienced by a student of @jfalip after deleting a non terminal document.