Guard starting separately. Use try/finally for slot_sync
Change to not explicitly check for null

The implementation does this already
Remove superfluous comment
Use UTF-8 as default charset
Fix issue #109 - Make ZMQ.Context and ZMQ.Socket implement java.io.Closeable
Merge pull request #110 from trevorbernard/master

Various improvements
Fix issue #58 - XPUB can receive multipart messages
Merge pull request #111 from trevorbernard/multipart-xpub

Fix issue #58 - XPUB can receive multipart messages