Brooklyn node and cluster upgrade

Merges #266 (cluster upgrade) with work I've been doing on node upgrade.

Builds on #260 so please ensure that is merged first.

Needs further testing (by me at this point) but wanted to push it in case @neykov you have comments, especially on the last commit.
Don't like this class name because it clashes with `java.util.concurrent.TimeoutException`. That will just confuse people, including when looking at code and when writing catch blocks. How about `RuntimeTimeoutException`?