Store a log of installed & uninstalled packages into a permanent storage
Add a flag to activate storage of installed & uninstalled packages into a file. Use that flag in the updater.sh script.
This has a slightly different format than the previous version of updater. Furthermore, it contains markers starting and terminating a transaction.
This is for #117 (closed).
The branches of the MR are chosen so the correct range of commits is show. The real merge would be to updater-ng.