Moving lint and build into test dependencies.

[gauntface]

R: @jeffposnick @addyosmani

Fixes #115

One problem I hit is that gulp-eslint seems to exit the gulp process early. I stumbled across a hack to make it work by adding gulp-debug to the pipe chain, but I'm not sure what the problem is.

But this change does mean testing will always be run against a new build and linting is now part of the test task.

[jeffposnick]

Regarding the gulp-debug bit, I'm diving into what's going on to try to isolate the source of breakage independent of this PR.

I have a minimal reproduction of the aborted gulp process when just running a gulp lint project='sw-lib' and gulp lint project='sw-precaching' against the current master, with all the other projects seeming to complete without issue.

I'm going to poke around a bit more to see what those two projects have in common w.r.t. linting. (I feel like this might be why, when I run gulp lint locally, it doesn't pick up some of the things that Travis CI picks up—gulp lint is also aborting early, while Travis CI now does per-project linting.)

I'd like to hold off on merging this PR until we can clean up whatever that issue is, and then we can hopefully omit the gulp-debug hack.

[gauntface]

Would you accept this PR if I remove lint from the test task?

I specifically wanted build and test to work together, linting was a nice to have.

[jeffposnick]

Yes, if you could remove the linting and the hacky bits, I'd be fine with this PR. I'll file a separate issue to investigate what's going on with the linting failures.

[jeffposnick]

(See #119)

[jeffposnick]

👍