Wampy

- adds support for WAMP `options` when sending a Publish `Message`
- update CONTRIBUTORS.txt

- adds connect to a Router by a URL
- adds Transport decision by URL protocol/scheme not on Client init
- adds quick start connection details to README
- adds detailed connection details to ReadTheDocs
- adds simple Router representation for Sessions based on the given URL when a Router instance is not provided to a Client
- removes forgotten features of ``MessageHandler``
- ``MessageTypeMap`` now maps to classes instead of strings
- adds test cases for URL handling
- minor tweaks to logging, layout and Exception handling
- adds more internal docs and comments

- instead of registering Roles as functions, register a reference to them and allow clients to decide how the actual implementation is looked up (to support nameko-wamp)
- remove ``TopicProxy`` because this can be (and should be) implemented on the client application now (see nameko-wamp for an example)
- remove dead test modules
- ``register_roles`` promoted to a public API on a ``Client`` that can be over-ridden by applications who want to control how their app registers Roles.
- update TLS docs

- Shared Secret Authentication (static)
- fixes: README URLs in examples
- simplify message classes
- pluggable message serializer
- pluggable transport
- remove unnecessary ``wamp_code`` on each Message
- add WAMP protocol for reference
- fixes multiple crossbars running in test suite
- simpler TLS
- simpler ``Session`` construction

- added remote Exception handling
- ``MessageHandler`` moved to the ``Session`` object to reduce miss-direction in RPC call protocol
- No behaviour now on a ``Message`` object - all behaviour is on the ``MessageHandler``
- remove "call with meta" as patterns such as this should be implemented by overriding the appropriate method in the ``MessageHandler``
- added some docs on the ``MessageHandler`` and how it can be used to customise wampy behaviour
- remove ``CalleeProxy`` as this is never used, no use-cases have been presented and maintenance is annoying
- remove all message handling from the ``Client`` and delegate to the ``Session``
- much internal tidy up and miss-direction removed

- change license to MPL 2.0
- add Client test fixture
- use Crossbar as default Router to reduce the barrier to entry
- improve and update docs