[Documentation] Explain cookie plugin is included in externals

[Rwhitbeck]

The Tabs documentation under dependencies links to the cookie plugin onto the plugins site. This is good but it would also be great to know that the cookie plugin can be found in the development-bundle > external folder from the download builder as well.

I'd also recommend mentioning this on the options page for the cookie option. Sort of a disconnect there when it says you need the cookie plugin but not told where to find it.

[Rwhitbeck]

Updated docs.jquery.com with updated cookie information

​http://docs.jquery.com/index.php?title=UI%2FAPI%2F1.8%2FTabs&diff=20694&oldid=20581

waiting on jqueryui.com update.

[Rwhitbeck]

Also sent pull request ​https://github.com/jquery/jquery-ui/pull/161

Updated cookie demo for Tabs to add more information that the cookie plugin is required and where to find it.

[Rwhitbeck]

Bug #7144 might make this invalid.

[Ralph Whitbeck]

Tabs: Updates cookie demo to include more information on how to find cookie plugin. Fixes #7172, [Documentation] Explain cookie plugin is included in externals.

Changeset: 4d557092ffe070c0c52a852530d3947436175539

[Ralph Whitbeck]

Tabs: Updates cookie demo to include more information on how to find cookie plugin. Fixes #7172, [Documentation] Explain cookie plugin is included in externals.(cherry picked from commit 4d557092ffe070c0c52a852530d3947436175539)

Changeset: c9341a3619a56fabe2025761961b39f0d661db0f