Moved signals.py into models.py, since this is always included
Introduced RedisMessage to wrap different kinds of messages into a managing class
Added option to echo messages
Readded get_prefix(), used by RedisPublisher
Using RedisMessage in unit tests
missing dependency
Adopted docs for message echoing
Enabled error logging
Added Python 3.3 to supported languages
Support for Python-3.3
Merge branch 'master' into echo-message
for the present, dropped support for Python-3.3
Added security check callback, in order to reject subscriptions to forbidden channels
Added callback function to reject subscription/publishing channels
branch echo-message active on Travis
Merge branch 'echo-message'