Small updates

Hi,

I've made some changes to make easier working with code:

- Added `websocket` gem to gemspec as dependency(that's why it's called 'dependency manager' ;)
- Added Gemfile (it's nice to test with bundler - especially that it is current standard)
- Moved renamed test folder to spec - that way RSpec will handle it much easier
- Added Rakefile with some 'basic' functionality:
  - `rake spec` will now test project
  - `rake release` and other will manage gem releases

My suggestion is to add travis.yml and start testing on [travis-ci](https://travis-ci.org) if you are not doing it yet - continuous integration is probably good way to go(plus you will get nice badge for free ;)

Nice work btw!