Add "custom query" functionality for changesets

[guillaume.tardif@…]

I think it would be really useful to have the ability to quickly define queries on changesets, similarily to what can be done on tickets (ie. with a GUI allowing filters on changeset comments, author, file path and commit dates).
This page should also implement RSS feed (as Ticket custom queries), to allow notification of specific changes.

I suppose that the implementation would be similar to the ticket 'custom query' page (but I havn't looked in depth at the code, not being a Python developer... yet). I leave it to the TRAC people to set milestone, priority, etc. Many Thanks for this great software BTW.

[cboos]

That's an interesting proposal.

[cboos]

This feature would also be a must for people (ab)using the TracReports for getting reports over changesets, before we could phase out the SQL reports.

The TracDev/Proposals/DataModel should make this possible.

We'll also have to think about whether queries should work on different types of objects. This could eventually lead to a merge of the Search module in the TracQuery module, as currently the Search module is performing unstructured search over different type of objects. See also #3375 for that.

Finally, the TicketQuery language should be generalized to make it possible to work on any kind of resource in the system.