Update Grunt configuration some.

The Grunt configuration for Backbone.Picky is a bit out of date. This 
attempts to update it in a minimal, just-make-it-work way.

* `grunt.js` renamed to `Gruntfile.js`
* Update project version in `package.json`
* Add jshint and uglify dependencies as they are no longer bundled 
  directly into Grunt
* Use `package.json` version in Gruntfile banner text
* Update rigger, uglify and jshint configurations
* Use new `grunt.registerTask` interface
Remove `.rvmrc`, replace with standard version files.

`.rvmrc` files have been deprecated, to be replaced by `.ruby-version`
and `.ruby-gemset`, a format which is apparently shared across ruby
version managing tools.
Add Rake to Gemfile, update Gemfile to use SSL source
Unpun SingleSelect and Selectable events

Both `SingleSelect` and `Selectable` fire `selected` and `deselected`
events, making event capture on a collection more difficult, as you get
twice the events you want, with different parameters.

Update Selectable's `selected` and `deselected` events to provide the
model as its first parameter (like how the collection `selected` event
behaved previously).

Change `SingleSelect` to fire `select:one` and `deselect:one` events
instead of the `selected` and `deselected` events. This is roughly
similar to the namespacing of the `MultiSelect` and so maintains a
foolish consistency.

Also:

* Update the tests
* Update the Readme documentation
Merge branch 'refs/heads/add-rake-dependency' into dz
Merge branch 'refs/heads/update-rvm-config' into dz
Merge branch 'refs/heads/singleselect-events' into dz
Merge branch 'refs/heads/dz'