Add support for receiving fragmented STOMP frames.  These can orginate from
frames that exceed the maximum WebSocket message size or from the node.js
overTCP function, the 'data' callback does not preserve message boundaries
at all so fragmentation can happen much more frequently.

Addresses issue #55
Merge pull request #77 from jmesnil/issue_55

Add support for receiving fragmented STOMP frames.  These can orginate f...