Upgrade to Jasmine 2.0 for server tests

The reason I am not using grunt.util.spawn here is because it swallows all stdio and is not configurable to inherit stdio from the process. Using child_process directly, which is what grunt.util.spawn does under the hood allows us to configure stdio as we please, i.e. preserver output colors, disable the annoying stderr messages being spit out by passing tests, etc.