More robust untarred directory finding

So far it was assumed the the unpacked directory matches the tarball
name, but this isn't always the case.
Also refresh patches applying with fuzz

Previously, the regexp was to strict and only allowed refreshing patches
with offset.
Quilt unpacked tarball name can have arbitatry name

The previous assumption that it matches the package name was just wrong.
Includes some other finy fixes.
Better abort criteria

If there are no local patch files, we don't need to run. Furthermore, in
case of several spec files, if one of them doesn't apply patches
(according to "quilt setup" output), we can skip it.