AUI-1226 Change button sizes from .btn-[mini|small|large] to .btn-[xs|sm|lg] on Bootstrap 3
AUI-1224 Add .glyphicon and change prefix from .icon-* to .glyphicon-* on Bootstrap 3
AUI-1223 Use <span> instead of <i> when creating icons on Bootstrap 3
AUI-1221 Remove .btn-inverse since it has been deprecated on Bootstrap 3
AUI-1222 Add .form-control to inputs and selects on Bootstrap 3
AUI-1220 Add .btn-default to .btn elements with no other color on Bootstrap 3
AUI-1225 Import Bootstrap 3 into a new module and remove Grunt bootstrap task
AUI-1228 Improve demos using extra Bootstrap 3 classes
AUI-1229 Change ProgressBar inner element class from .bar to .progress-bar on Bootstrap 3
AUI-1230 Improve ImageGallery button alignment and general spacings on Bootstrap 3
AUI-1233 Use .btn-toolbar instead of .toolbar as container class on Bootstrap 3
AUI-1234 Change Pagination CSS class from container <div> to content <ul> on Bootstrap 3
AUI-1235 Change grid system from .span-* to .col-[lg|md|sm]-* on Bootstrap 3
AUI-1239 Change grid system from .row-fluid to .row on Bootstrap 3
AUI-1240 Remove .container-fluid because everything is fluid on Bootstrap 3
AUI-1241 Fix Scheduler views toolbar alignment
AUI-1238 Migrate Modal markup to Bootstrap 3

Bootstrap 3's modal structure has 3 containers: .modal, .modal-dialog and .modal-content. The '.modal' container is not important for AUI though, and it would make the integration a lot more complicated, so I've just removed it and I'm making the widget work with .modal-dialog and .modal-content as the bounding box and the content box respectively.

With this the modal's features work as expected. There are just a few more Bootstrap css changes that we may want to incorporate later, but decided to leave out for now as users can do that in their code if necessary. The changes are:
(1) .modal_content doesn't have the 'overflow: hidden' rule anymore, so resizing to make the modal very small will show contents outside the modal.
(2) .modal-dialog has 'margin: 30px auto' by default, so resizing will grow both sides of the modal at the same time now.
(3) .btn-toolbar now clears float by default, so the close button takes more space than before, pushing the header content down.

Regarding (1), another thing we can do is allow the user to specify min width/height through ResizeConstrained plugin. We need to change AUI's modal to allow for this yet though, since ResizeConstrained needs to be plugged in after the Resize plugin and the modal isn't doing that yet.
AUI-1232 Fix vertical Toolbar border-radius on Bootstrap 3

Vertical toolbars can't use the btn-group css class, they should only have btn-group-vertical instead, so changing our javascript to work accordingly.
AUI-1243 Remove Rating's underline on hover
AUI-1244 Use .form-control instead of .control-group on Bootstrap 3