Skip symlink for /proc if inside Docker and chroot

In our use case, we have a Docker container (because of our CI) that runs debootstrap inside a chroot. We ran into issues with mounting /proc in this environment. The error we were seeing was "Too many symbolic links" because mount was detecting that /proc was a symlink to itself.

This change skips the creation of the symlink if you are inside Docker and a chroot to avoid the above error.

Please let us know if there are any changes you'd like to make.

Co-authored-by: Joshua Aresty joshua.aresty@emc.com Co-authored-by: Nicholas Calugar ncalugar@pivotal.io