Bugfixes bundle

[jmico]

Note: this pull request already include bugfixes from bobtfish and clintongormley.

• Stop leaking memory.
• Performance optimizations for publish.
• Defer finding the path of the included spec file.
• Fix for server asking to close the connection.
• Fix a race condition stopping connections from closing properly.
• Fix a bug when closing a channel that is subscribed to multiple queue.