Popup: Add widget() function.
Popup: Add option "class" which applies classes to the container (i.e., to widget()).
Popup: Support "enhanced" flag.
Integration tests: Popup: Parameterize popup-opens-and-closes test so other popups can be tested as well.
Demos: Add pre-enhanced popup example.
Integration tests: Popup: Test that pre-enhanced popup opens and closes correctly.
Integration tests: Popup: On the link it's data-rel, not data-role.
Demos: Popup: Change wording from "pre-enhanced" to "pre-rendered" to better reflect the concept. Thanks jzaefferer.
Popup: Heeding reviewers' suggestions. Thanks scott_gonzalez, jzaefferer, arschmitz.

- Better variable names
- Set attributes before attaching to DOM
- Reduce number of DOM insertions
Demos: Popup: Forgot data-role="page" on the pre-rendered popup example page.
Merge branch 'master' into popup-widget-review
Popup: Renaming option "class" to "wrapperClass".
Popup: Use this._delay instead of setTimeout().
Popup: Renaming variable "o" to "opts".
Demos: Popup: The word "pre-enhanced" was still there in one place.
Merge pull request #6135 from jquery/popup-widget-review

Popup widget review