Improve pass/fail indication in grunt output

Intern's grunt task now considers additional types of pass/fail message
when classifying task output. It also considers individual lines rather
than marking entire chunks of output.
Add "waitAfterComplete" option to remote runner

Setting waitAfterComplete to true in the test config file or from the
command line will cause intern to wait for the user to kill the test
browser when tests are run on a local Selenium server. It has no effect
when running tests on Sauce Labs.

Resolves #144
Rename `waitAfterComplete` option

`waitAfterComplete` is renamed to `leaveRemoteOpen` and is now command
line-only.

References #144
Forcibly close open sockets when closing the proxy

When `close` is called on the proxy, any sockets remaining open are
forcibly closed, allowing the proxy server to close.
Cleanup

References #144
Merge remote-tracking branch 'upstream/master' into bench