Show the package name as a technical package's name, and its short description as the comment.
This is necessary for displaying technical packages in the MSC, since sorting by short desc. takes 11 seconds on 50,000 packages.
With this change, I've also made all of the non-categorized app views (E.g. per-origin ones) display technical packages by default.
I'll probably also add a runtime toggle so that the "Provided by Kubuntu" entry doesn't become *totally* unnavigable if somebody doesn't care about technical packages.
As a side effect, the Muon Updater now shows the package name for the updates in the "System Updates" category.
The Package::controlField() checks we were doing in various functions for extras.ubuntu.com packages are kinda expensive.
To amortize this, we check if the package is an e.u.com package in the technical package constructor, cache the result, and only check the e.u.com control fields if it's verified to be an e.u.com package.
For another small speedup, do not run the names (short descriptions) of technical packages through i18n. The apt cache handles i18n for apt descriptions.
