fix(browser): reply "start" event

When a browser creates another socket.io connection, we forget the old one, however we need to reply all the events that happens in that connection. Somehow I forgot to reply "start" event, which caused the "Adapter did not report number of tests" warning.
style: make jshint happy

Conflicts:
	lib/server.js
feat(launcher): send SIGKILL if SIGINT does not kill the browser

In some cases chrome on linux does not die when it receives a SIGINT
signal. So after a SIGINT is sent, wait 2 more seconds and issue
a SIGKILL if the process is still running.
docs(config): clarify file expression examples