Fix assorted issues found by FindBugs.

There are a lot of fixes here (and lots of noise from whitespace), but some of the more interesting ones you may want to check:

1) Using Java 7-style "try-with-resources" blocks in some places where we weren't closing streams. (Breaks Java 6 compatibility, though it may already be broken.)
2) Removing Serializable from the interfaces of a few Server*Event methods that had non-serializable contents.
3) More error handling in the HttpReader.