Browser tests are usually hitting Travis log size limit

[evertonfraga]

Latest runs of test:browser have presented failures due to huge log output (when it hits 4MB mark).

The job exceeded the maximum log length, and has been terminated.

I believe that simplifying the test reporting using less bytes as output can solve it.

[alcuadrado]

I was also hit by this and tried my best to reduce the size of the tests' output. I should have opened an issue for future reference.

I don't know much about karma, so there may be lots of room for improvement.

[evertonfraga]

Fixed by #86