Added host and port exception handling for SocketStream

I've added some additional exception handling for both the host and port. I'm not familiar with Java.net, but I think that these should cover most error cases.

I'm not sure if there is a better way to handle the exceptions. Since I plan to use clojurescript adapters, I won't need to handle them - and I don't know what would best suit other projects.

PS. I apologize for the whitespace noise in the commit.