Remove/obscure communities feature

[cc-a]

At the current time there is no plan to provide the communities feature of Invenio to users. This should be removed/obscured from use. We should also investigate whether the communities feature can be co-opted to implement the library approval process.

@richard-jones adds: In the initial case we should review what's involved in achieving this

[richard-jones]

Impact analysis on the removal of this feature, and approaches to do it. To then be discussed on 23rd