createElement optimization should allow for tag pair as well as quick-closed tag

[kswedberg]

To take advantage of the document.createElement optimization when a tag pair such as '<span></span>' (as well as a self-closed tag) is passed into the jQuery() function, we can change line 35 of core.js (Rev. 6582) from this:

rsingleTag = /^{<(\w+)\s*\/?>$/,}

to this:

rsingleTag = /^{<(\w+)\s*\/?>(?:<\/\1>)?$/,}

Thanks, John, for the regex improvements!

[flesler]

I'm accepting the ticket so it won't get lost in the pile. I'll try to do this asap.

[john]

Fixed.  http://github.com/jquery/jquery/commit/c4c820efff4fa7bcce0d5bf0a448625278ea6379