Start work on 0.13.2
tmpfiles.sh: add support for + modifier

systemd added support for b+, c+, p+, and L+ in 2e78fa79 and 1554afae to
remove the target path if it already exists.
tmpfiles.sh: add support for C action

Recursively copies files or directories.  Added by systemd in 849958d1.
savecache: check permissions on the correct directory
runscript: move verbose mode setting near debug setting
localmount: unmount aufs branches
Use exception-based approach for cgroup/ulimit setup

Note from William Hubbs:
I spoke with Roy about this, and he pointed out that user-defined
functions may need the limits applied, so it is better to go with a
method that uses exceptions to determine which functions apply the
limits.

X-Gentoo-Bug: 522408
X-Gentoo-Bug-URL: https://bugs.gentoo.org/show_bug.cgi?id=522408
typo fix
man: Document start_inactive and in_background_fake