This was required for us to get assert.async() support within tests, as
well as assert.expect() support. This was required because we need them
for multiple async tests that are coming.
As jQuery 1.7.2 is the lowest version of jQuery supported by Select2,
it makes sense to run the tests on it. For the most part, we can
assume that the newer versions of Select2 are backwards compatible
enough such that this isn't an issue.
The recommended version of jQuery to use is the latest though, which
is why the jQuery file is only included in the tests.
This revealed a few issues with our data fallbacks and `.append`
functionality that was introduced in jQuery 1.8.
This adds decorator support in a very basic way, but enough that
it doesn't take a lot of effort to get it implemented.
This also starts work on splitting things out for theming.