Stop operations that modify the system when root.
Stop operations that modify the system when root.

makepkg does not allow to build packages as root, and
makes chaser quit.

Checking early has a benefit: if we wait until makepkg
is invoked, some operations such as creating the cache
directory or downloading packages are done as root,
causing issues for the next non-root runs, e.g. they
cannot access files. The user then needs to intervene
manually.

rshipp/chaser,rshipp/chaser