Proposal: support only one version of libraries

[Nicolás Alvarez]

Hi devs,

Currently many library packages in emerge contain rules in the .py
script to download multiple library versions, and there are
corresponding patches for all those versions. Sometimes those patches
are even identical.

For example, assuan2 has download URLs, digests, and cmake patches for
2.0.1, 2.0.2, 2.0.3, and 2.1.1. The 2.0.x versions date to 2011. Any
reason to keep them? I'd just delete everything except 2.1.1, which is
the default target.

I hereby propose keeping only the latest version and deleting any old patches.

-- 
Nicolás