fix(tests): Reorganized coverage tests

[hyperreality]

fix(tests): Reorganized coverage tests

Moved coverage configuration from karma.conf to the gulpfile:

• The server-side coverage tests are already configured in the gulpfile so I think the client-side ones should be too, cleaning up the karma.conf file.
• The previous method to tell karma to run coverage tests involved flipping an environment variable which karma.conf then read. I suspect that this is what caused client-side Travis builds not to send reports to coveralls

LCOV report file concatenation and sending to coveralls has been moved from the gulpfile to .travis.yml, as per @mleanos suggestion

• Now coverage tests can be run locally using gulp test:coverage without error if you don't have a coveralls account
• Unfortunately the Karma coverage summary cannot currently be printed to the console due to a bug (well, it can be printed, but it causes the karma:coverage gulp task to hang for about 30 seconds).

[coveralls]

Coverage increased (+9.8%) to 72.975% when pulling 301abe4 on hyperreality:gulp-coverage into 7be1910 on meanjs:master.

[hyperreality]

Boom! Looks like it's covering both client and server side tests. Now so long as it doesn't send out 9 more coveralls notifications...

[lirantal]

Cool, thanks!