[fink-core] upgrade process for big sur/dpkg1.16

[Hanspeter N. <fi...@sn...>]

What's the upgrade process for the dpkg1.16 branch and the dists tree?

Several packages are now essential (e.g. time-date-pm and xz) and will 
have to be moved from their present subfolders in dists to 'base'. Also, 
some base packages have newer versions than what's in the dpkg1.16 
branch source (e.g. libiconv and texinfo). But the dpkg1.16 branch 
versions have needed changes that might be incompatible with older fink 
installs, so we can't just copy what's currently in dist to the dpkg1.16 
branch, or push the dpkg1.16 branch versions directly into dists. Or are 
dpkg1.16 packages compatible with legacy dpkg?

Hanspeter