Refactored Client to be thread-safe.

No more @@class variables. They're shared across all instances of the
Client so the client was inherently thread unsafe.

The client is now instantiated, and each instance can have it's own API
key.

Also, docs and specs updated.
Updated README, added LICENSE and CHANGELOG.
Core ext (String) snake_case and camel_case.
Added Guardfile.
Renamed gemspec file.
Removed junk from Rakefile.
Remove refs to streaming code until completed.
Refactored Client to be thread-safe.

No more @@class variables. They're shared across all instances of the
Client so the client was inherently thread unsafe.

The client is now instantiated, and each instance can have it's own API
key.

Also, docs and specs updated.
Streaming support for various API v2 endpoints.

Connection is kept open and on each chunk the buftok is filled.
After the tokenizer recognizes a valid response, it can be parsed
(JSON).

Still need to integrate it with the rest of the library and convert
responses to actual Meetup types.
Merge branch 'streaming' of github.com:neektza/rmeetup into streaming