Demo on Github pages

Github is great and allows us to have a page for each project.

The [current demo page](http://cameronspear.com/demos/bootstrap-hover-dropdown/) has some 404 errors (probably #45 asks for this problem).

Now the demo page is moved in `gh-pages` branch that will be available on Github pages once this pull request is merged (I am not sure if `gh-pages` branch is merged automatically, if not, merge it manually).

The new demo page is here: https://cwspear.github.com/bootstrap-hover-dropdown/
The demo page for my fork is here: http://ionicabizau.github.io/bootstrap-hover-dropdown/

Thank you for this good plugin! :smiley: