Update readme with more information
minor: a few small gemfile tweaks

- removing redundant json gem in dev
- making guard notifications windows and linux friendly
reformat todo in readme
Add c extension for bson_int32?
minor: fixing copyright and license information
Merge pull request #1 from brandonblack/gemfile-fix

minor: a few small gemfile tweaks
Add extensions to gemspec
add build task to Rakefile
Add release task to Rakefile
Remove cucumber
Remove cucumber task
Remove finished refactorings