docstring fixes and setup.py cleanup
Merge branch 'master' of github.com:pika/pika
New method signature for constructing connections

- connection.Connection
 - New argument: on_open_error_callback
 - Switch to constants for callback names
 - Rename Connection._connect to Connection.connect
 - New method: Connection.add_on_open_error_callback
 - Move connection try handling into the logical connection.Connection class instead of low-level base_connection.BaseConnection class
- Raise a deprecation warning if someone tries to use Connection._connect

BaseConnection
- Reflect API changes in connection.Connect in constructor
- Streamline adapter_connect
- Make adapter_connect iterate through all resolved IP addresses for a given hostname, adding support for IPv6
- Reset connection state at the end of _adapter_disconnect
- Handle SSL errors in create_and_connect to socket
- Create consistent logging output in create_and_connect_to_socket
- Remove some vars out of init_connection_state

AsyncoreConnection
- Add support for the new API signature for connecting

BlockingConnection
- Dramatically lower the write to read ratio to better respond to heartbeats in write heavy applications
- Block any calls to add_on_open_error_callback as the user should catch the exception instead
- Add a BlockingConnection.connect specific method bypassing the reconnect logic in Connection.connect
- Fix the indent in disconnect
- Remove callbacks in _adapter_connect so that the connection error callback is not invoked
- Remove various logging statements

SelectConnection
- Add support for the new API signature for connecting

TornadoConnection
- Add support for the new API signature for connecting

TwistedConnection
- Add support for the new API signature for connecting