Since we no longer have suggest/recommend rules and no longer use any update
or feature rules so packages are removed by default, we do not need weak rules
anymore.
As it is faster to remove packages from the repos and keep them out of the
package pool to begin with, we don't need an installable() method on the
policy.
Updating does not work yet. The test case works fine for installing/removing
the correct packages however. Weak (update/feature) rules are entirely ignored
so far.
Watches are on literal ids rather than literals to save on function calls
and memory usage. So a few methods for literals now have an id counter part.
This should probably be refactored to have the literal versions call the
id ones instead.
Jordi Boggiano
Nils Adermann
Leszek Prabucki