Set identity to hostname if not explicitly set

Closes #16
Raise exception when required pycrypto is missing
Work with plugin.activemq.base64 configurations

Fixes #17
Add tests for ActiveMQ base64 encoding

And modify existing tests to support message verification
Increase timeout for integration tests

So it helps preventing intermittent travis-ci failures
Review BaseConnector use_b64 property

It should false for all connectors but ActiveMQ and use
Config#getboolean method for it. Adding unit testing for that.
Merge branch 'jmetzmeier-upstream-bound'

closes #19