Allow passing config file to karma run

[mvolkmann]

I'm having a tough time getting this set up for the first time.
I generated karma.conf.js using "karma init".
port and runnerPort are both set to 3000.
When I run "karma run karma.conf.js I get "There is no server listening on port 9100".
I don't know where it is getting 9100. That must be a default that I am failing to override.

[dignifiedquire]

I'm afraid currently it's not possible to read out the configuration, though it would be nice to have that. Try

$ karma run --runner-port 3000

[vojtajina]

You can't set both ports to the same value. (We should get rid off the runnerPort and merge them, but that's not done yet).

As @dignifiedquire pointed out, when using non-default runnerPort + karma run, you need to pass it as an argument.

'karma run' should allow passing the config file and read the port from there, so I'm changing the title of this issue to fix that.