Fix Travis errors - karma and mocha

A few things:
- as in #245, path for angular-ui-utils required update in karma.conf
- unit test failed because of missing linkedin config for `test` env
- last user model unit test failed because `provider` must be set for validation to occur, and simplified
- Gruntfile still had reference to `jade` - merged path with existing `html` task
- Gruntfile - excluded `test/coverage` from jshint