Support bootstrap v4 beta changes

[eamodio]

Now that bootstrap v4 beta is finally out, it would be great if this could align with it :)

[sschocke]

Yes, aligning would be nice, considering the typeahead component does not even work anymore in bootstrap v4 beta

[tochoromero]

Yes, I need to sit down and upgrade to Bootstrap 4 beta.
Now that Bootstrap 4 is in Beta, and is more or less production ready (I have been using it for my projects for a while now) I will drop support for Bootstrap 3. I just don't have the time to support both versions.

[thejaff2]

Im currently not getting typehead working with bootstrap v4 beta, is this a known bug or am I doing something wrong? (Downgrading to v3.3.7 and NOT setting config.options.version = 4 is working for me)

[lukpep]

@thejaff2 - it's known - #40
same for me

[stuartbale]

Bootstrap v4 is now at version 4.1.1
(see https://getbootstrap.com/)
Is it likely that you will update this project, or is it now abandoned?