We were repeating the same code over and over (with a few variants) to
setup tests which require an administrator. We can use a tag and
simplify the code.
In some tables, we had "actions", and some columns were also links
pointing to some places. Having both of them at the same time is
confusing, particularly since traditionally the links in the columns
pointed to the same place as some of the actions (although that's not
the case since commit 48db31cd).
We're still keeping links in tables which don't have an action column.
For instance, the proposals table has a "select" button which would be
harder to use if we had action buttons next to it.
