Hydra recipe for LibreJS

[Nik Nyby]

Hi hydra-users,
I think the GNU LibreJS project could benefit a lot from using some sort
of continuous integration. LibreJS has an extensive test suite, but it's
sort of a pain to run manually - It takes like 5 minutes to complete, it
opens a bunch of tabs in your browser. I'm looking forward to automating
the process.

Hydra seems like the natural choice. I haven't been able to come up with
a Hydra recipe for LibreJS yet, since I need the CI server to be able to
run:

- Iceweasel, or Firefox, Abrowser, etc.
- Mozilla's cfx tool:
  https://developer.mozilla.org/en-US/Add-ons/SDK/Tools/cfx

Can someone tell me if the Hydra servers have X installed, and if it
sounds do-able to run the LibraJS test suite on the Hydra servers?

Thanks,
Nik