Deprecate the Twitter bootstrap helper

[jroper]

The Twitter bootstrap form template helper wasn't updated since a year and does not yet fully support Bootstrap 2.
In a pull request guillaumebort suppose to deprecated the helper in the next Play version (and publish a Plugin for the helper?).

But in Play 2.1 the Play Template helper Documentation still suppose to use the Twitter template helper and there is no note that Bootstrap 2 isn't fully supported which is frustrating for newbies like me.
@Gissues:{"order":66.6666666666666,"status":"backlog"}

[ndeverge]

First, I'd remove or deprecate the paragraph from the documentation.

[huntc]

Probably should also be factored out of the core of Play as well.

[wsargent]

I can take this -- I'll refactor it out of Play Core, mark it deprecated and move the documentation out.

[wsargent]

Most of the work is done, but there are some outstanding jQuery issues in the "forms" sample applications. https://github.com/philipmjohnson/play-form-kludge looks like an interesting approach as well.

[wsargent]

jQuery issues fixed.

[wsargent]

Needs a note in the migration guide as well.

[benmccann]

The Play 2.3 migration guide mentions this has already been deprecated: https://www.playframework.com/documentation/2.3.x/Migration23

Closing this issue as addressed