* update-bulk:
This rebuilds all pkgs in system repositories that are outdated.
with this xbps-bulk is now considered fully obsolete.
* update-sys:
This rebuilds all pkgs in system that are oudated and once built,
updates them via xbps-install(8).
This target defines a new configuration option "XBPS_SUCMD" that
is the command to execute to update the system. By default set to
"sudo sh -c".
CAVEATS
- need to check if binpkg is in local repo.
- need to add support to specify alternative rootdir.
- need to add support to specify system repos.