Bootstrap 3 upgrade

* Change column classes to be 'col-md-n' business instead of 'spanN'
* Change modals to have some extra classes
* Change alert-error to alert-danger
* Update javascript to use namespaces as in bs.popover
* Plop in the new simple_form_bootstrap wrapper stuff
* Use datatables' bootstrap 3 styles instead of bootstrap 2
* Restyle all forms to have .form-control etc when needed
* Wrap many forms in col-md-6 so their width: 100% controls dont go crazy
* Tweak anything with height+padding to consider border-box sizing