[entropy.client.interfaces.repository] drop is_root(), this is always running as root
[entropy.db,entropy.spm] rewrite SPM package metadata update code

This commit moves all the SPM package metadata update logic, including
pkgmove and slotmove to entropy.spm plugins.
This makes possible to handle the event more reliably. In particular,
Entropy now controls what Portage does, basing on the repository treeupdates
information.
The scenario in where the Portage tree was not updated and the called
"emaint --fix moveinst" did not do what it was supposed to do is now
handled correctly.
[equo] do not automatically remove unmaintained packages, unless --purge is passed

This addresses the case in where the user may not have run equo with --ask
and unmaintained packages get removed without user consent.
[client] update entropy.pot
Release Entropy 182
Tagging Entropy version 182
[matter] builder: use cls. and self. in classmethods and methods
[matter] query binpms when determining the availability status of an injected package
[conf] drop optusnet.com.au mirror from repositories.conf.d/
[conf] drop the "remote web services server url" part from repository "repo =" param

This has been deprecated for long time.