In the form handler logic for `edit-tags.php`, don't redirect until `$_REQUEST['paged']` has been checked. All `switch` cases (except `edit`) now use `break` instead of `exit`. 

Fixes #16162.

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git-svn-id: http://core.svn.wordpress.org/trunk@29554 1a063a9b-81f0-0310-95a4-ce76da25c4cd