Don't chomp on an empty file
Guard sync_mounts against containers with no lxc.mount.entry's
If container's config uses lxc.mount.auto then set it to proc:rw sys:rw

Centos containers in particular use proc:mixed sys:ro which
prevents changes to kernel parameters so this needed to be changed
to let Chef package installation set parameters as needed.
Disable certain sysctl.d files in Ubuntu 10.04 instead of renaming procps

I was wrong. /etc/init/procps in Ubuntu isn't the problem.
Certain /etc/sysctl.d/* files in Ubuntu 10.04 cause
`start procps` to fail so just disable them.
Bump version to 0.2.3