Upgrade travis to trusty / containerised

[lathonez]

Atm we're stuck on 12.04 because we're using sudo.

dist: trusty doesn't seem to work, it should according to the docs, I'm thinking it's cause of the android language which isn't mentioned on the trusty env page

Upgrading (to trusty in particular should bring the following benefits):

• no need to install npm as it will come bundled in the mega image
• use latest chrome (etc)
• quicker builds

If we can't upgrade to trusty for some reason, we should look at upgrading node without sudo, which should get us onto the containerised structure

[lathonez]

travis-ci/travis-ci#5370

[lathonez]

Gone the other way and upgraded to 14.04 by disabling android for now. I think it may be easier to try to install android manually here than fight all the other workarounds.

On the positive end we can now use nvm to pick a good node version (4.1.*) and don't need to hack around with google

[lathonez]

So TODO is install somehow install android.. Kind of depends if we ever get a response to that travis issue too.

[lathonez]

https://github.com/lathonez/clicker/blob/master/.travis.yml#L58-L63

Can't move onto docker yet as they're using 12.04. As soon as the move to trusty it should be sweet as we're not using sudo anywhere now.