Connection: Add documentation and stub for on_each_data() and on_next_data() methods.
Connection: implement on_each_data() and on_next_data() methods. Add test for these methods as "receive_data.t"
Merge remote-tracking branch 'remotes/ito/connection_raw_data' into better-unicode

Conflicts:
	lib/AnyEvent/WebSocket/Connection.pm
use mojo_ prefix for mojo test
new Message class
replace on_* with on
s/data/message/
use is_* methods instead of type attribute for Message class
doco
deprecation warnings
documentation
Connection send method can take a Message object
doco