Add option to use thumbor?

[sylae]

A common problem on the chat is people (myself included, sorry!) posting images that are...large. Not only does it fill the screen with an occasionally-undesirable image, it also wastes client bandwidth.

Since a couple days ago, I've been using a thumbor install to resize stuff for files.calref. It would be a nice option to add this to cadence, if possible. I'm not too familar with New Cadence, but the easy fix would be to just change the [img] tag parser a bit? The hard fix would be adding a user customization option to that to toggle thumbing incoming images (which we should do if this is a thing that interests people).

Thumbor itself is really simple, just prefix the existing url with something like:

http://thumbor.tld:port/500x500/smart/(original url)

and it'll do the rest :)

[cburschka]

The magic of cadence2's config system allows us to override xbbcode tags directly from the calref.yml install profile, so I'd suggest using the outgoing option. (Incoming would require changing a whole bunch of code, and since thumbor afaik requires you to set up your own server, it'd be a bit impractical to put it in the upstream code.)