Don't update a package if the vendor string is different

[RedDwarf]

In openSUSE "zypper -v up -t package" will not update a package if the newer version has a vendor string different than the installed package. It can make two vendors equivalent adding a file in /etc/zypp/vendors.d/, but in general the rule applies.

This behavior has proved to be very useful, it has avoided me the need for 54 package specific priorities I have in Smart. So it would be good if Smart implemented something similar.

[Anders F Björklund (afb)]

Smart's Package currently doesn't have a getVendor() - possibly because there is no such thing in .deb packages (it only knows of maintainers), so that would be the first thing to add.