programs/uninstaller: check HKCU for uninstall entries [Try #2]

[Tom Spear]

Submitting for approval to here before I send to wine-patches

This pretty much changes most of the functions in the uninstaller to
handle arrays so that we can actually handle scanning HKCU as well as
HKLM.

In my tests, this did not break anything, and allows entries listed in
uninstall for both HKLM and HKCU to be seen, as well as allowing them
to be uninstalled.  This version of the patch does not duplicate code,
like the old one did, and causes no additional warnings when
compiling.

Comments, questions, feel free.