Allow local file system detection to handle bind mounts.

[bbockelm]

Bind mounts are like a symlink on steroids - they allow admins to
graft part of the filesystem tree onto a different portion.

They show up as filesystem type "none", which we currently interpret
as a non-local filesystem.

With this patch, if a bind mount is detected, we lookup the source
of the mount and re-run local file system detection on that directory
instead.

Thus, if the bind mount is of a local filesystem, then we correctly
declare it local. This patch was tested on a T0 VM which hit this
issue.

Recursion is used (so bind-mounts-that-have-bind-mounts are OK);
patch includes cycle detection (although I'm not sure how one can
form a cycle, but I hate infinite recursion).

This is a forward port of #8813.

[cmsbuild]

A new Pull Request was created by @bbockelm (Brian Bockelman) for CMSSW_7_4_X.

Allow local file system detection to handle bind mounts.

It involves the following packages:

Utilities/StorageFactory

@cmsbuild, @Dr15Jones, @ktf, @nclopezo can you please review it and eventually sign? Thanks.
@Martin-Grunewald, @wddgit this is something you requested to watch as well.
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@Degano you are the release manager for this.
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