Start client implementation (issue #2)

- added a trivial client example (turnpike/client)
- welcome message takes server ident as a parameter
- TYPE_ID_MESSAGE ==> MESSAGE
Start adding CLI for client (issue #10)
Fixes #7
Basic CLI for client working (#10)
Merge branch 'master' of github.com:jcelliott/turnpike

Conflicts:
	server.go
	wamp/wamp.go
Update README.md
Move turnpike/wamp package to turnpike

- this makes importing turnpike easier
Add function for server to send an Event message

- Default log level to info
Provide a function for using an external logger
Skip handling malformed message

- Prefix server log messages with 'turnpike'
Remove redundant string conversion
Add connection write timeout and rotate messages

- drop old messages when client is backlogged
- increase default server backlog
Add simple example using autobahn.js to connect to Turnpike

- issue #11
Add license (MIT)
Possible fix for autobahn.js changes
Reference package with full URL
Add newId function to generate a call ID.

See AutobahnPython Clinet implementation for reference:
https://github.com/tavendo/AutobahnPython/blob/master/autobahn/autobahn/util.py#L65
Merge remote-tracking branch 'upstream/dev' into mp-fix_examples
Merge remote-tracking branch 'upstream/dev' into mp-add_client_id_generator
Add callback on session open (WAMP welcome message)