Object cache the results of getting translation jobs

[joehoyle]

We now grab all the jobs for an object at once regardless of status, then filter them later. This way we get a much better cache hitrate.

Also added invalidation on deleting a job and creating jobs for a post.

See #234

[simonwheatley]

This looks good. Are there any tests it's appropriate to add here?

Let's wait until #271 is merged before merging this.

[joehoyle]

• [x] Add some unit tests

[simonwheatley]

@joehoyle bump

[joehoyle]

@simonwheatley @johnbillion it seems we are running tests twice right now, once for pull-requests and once for each branch, that means we have two builds on every pull-request. On other projects, I've typically turned off the "test every branch" option in Travis, so we only have to have the single PR build.

Other than that - this PR should be good to go, added tests!

[simonwheatley]

@joehoyle @johnbillion Can you please refresh the branch so it will merge cleanly, please?

[joehoyle]

@simonwheatley done! just waiting for the build.

[joehoyle]

Doh, I guess there was some pretty big changes merged in. I'll take a look at this tomorrow.

[simonwheatley]

@joehoyle Thanks! :smiley:

[joehoyle]

@simonwheatley phew, got there! I think the merge from develop didn't bring the add_action changes with it. Passing now.