WebAdmin: resync from the web interface

[Manuzhai]

It would be nice to be able to resynchronize from the web interface. I've written a WebAdmin component that does this for any repository that supports the 'sync' method.

(Should we have a WebAdmin component for tickets?)

[Manuzhai]

Adds a Resynchronization module to WebAdmin.

[markus]

Looks good IMHO. But what I'm missing is an interval option, see #1271 for cboos' proposal.

[cmlenz]

Resync can potentially take quite a long time, so I'm not sure it's a good idea to do this from a request handler.

I'd also put this functionality on a Version Control page, that would in the future probably allow other types of operations (such as selecting the repository type and directory/URL).

[Manuzhai]

I like the idea of calling it Version Control.

About the request taking too long: do we have data on how long resync takes on very large repositories? What is the risk that the resync takes longer than the timeout?

I quite like the idea of interval resyncing, this would also make it not take so long. I'm thinking I would just do one field that says how many revisions to resync. Could default to say, 10 revisions. Possibly, we could impose an upper limit on the number of revisions that can be resynchronized from the web, so we're sure it doesn't take too long.

[cboos]

resync, and other version control operations like changing the scope of the repository (or adding/remove repositories, see #2086) should certainly deserve an admin module.