Pass through mocha command line options

[ForbesLindesay]

Many of mocha's command line options I don't care that much about, but it would be very very helpful to pass through:

-b, --bail                      bail after first test failure
-g, --grep <pattern>            only run tests matching <pattern>

Also of some (limited) use would be:

  -i, --invert            inverts --grep matches
  -t, --timeout <ms>      set test-case timeout in milliseconds [200]
  --debug-brk             enable node's debugger breaking on the first line
  --globals <names>       allow the given comma-delimited global [names]

[domenic]

Agreed, this would be a good idea. I'll probably try to pass through everything. Pull request welcome of course.

[ForbesLindesay]

Awesome thanks :)