Move the 3 Search Bar options into their own popup menu.

Opening the search bar causes the terminal width to be increased due
to the length of the three Search Bar options text.
Ideally, this should be redone using .ui file (consider looking at the
KHTMLFindBar code in kdelibs).  The Search Bar in general needs some
rework.

BUG: 211550
FIXED-IN: 4.7