Update debug dep to ^1.0.2 so it can be npm deduped
Make socket.io-client conditional.

Even if you only run with serveClient(false), you still
need to have client come along for the ride.  Normally,
this is just fine but I have a case where ditching the
extra 2.3MB client is required.

With this PR, you can safely remove client from
node_modules if you need to.  Leaves existing functionality
in tack (client version and source are lazily loaded
if serveClient true).
Merge branch 'client-dep-conditional'
Merge branch 'update-debug'