Easy administration mode for Alaveteli sites

[RichardTaylor]

If a site doesn't have the resources required to administer the site for a period, one could envisage an "easy administration" mode which the site could be placed in.

In such a mode the site could:

• Prevent signups by anyone other an a Pro user.
• Prevent new requests and annotations from anyone other than a Pro user.
• Prominently advertise the reason for a site being put in such a state and call for donations/volunteers/funding.
• Adjust the contact-form and contact details to further deter/negate the need for contacts as far as possible.
• Stop showing user names on the site other than for Pro users who've explicitly requested it.
• Run a censor rule on all requests to make a best-effort to remove users' names from the request correspondence (other than for Pro users who've explicitly requested this not to occur on their requests).

The latter two points are aimed at reducing requests from people asking for their names to be removed from the site.

Having such a mode could be used for fund-raising / seeking volunteers - campaigns could be more credibly linked to enabling the service to continue if there was a system in place for ~"turning it off".

Putting a site into such a mode for a period of time could be a precursor to putting it into a static archive mode - from which a static copy could be obtained.

[garethrees]

Note some extra ideas in https://github.com/mysociety/alaveteli/issues/6190.