The flat profile function list cuts down the number of
entries to a few hundred to keep KCachegrind responsive.
In Qt3 (and Qt4 compat) lists, KCachegrind only resorted the
inserted few hundred entries when clicking on a column header.

This commit fixes the bug by using a Qt4 list model for the
functions to show, implementing a custom sort function considering
all functions.

Still some annoying and missing behavior, such as
* column widths change on resorting
* keyboard handling missing

svn path=/trunk/KDE/kdesdk/kcachegrind/; revision=1124701