[Rpm-maint] Reserve RPM tags for ALT

[vseleznv at altlinux.org]

Hello, rpm-maint@!

Here is simple part of contribution that contains just tags reservation.

For now for RPMTAG_IDENTITY we want to store SHA1 sum of significant header
tags in modified BASE85 representation with alphabet of symbols that can be
used in RPM package provides and dependencies. The significant header tags are
all the package header tags except the tags that contain insignificant
information for its purpose (like RPMTAG_BUILDTIME). So there is black list tag
filter.

I'm not sure when we'll send next part, but it will probably contains draft
patches.