Add mount-point suggestion from Douglas Russell (Fix #9801)

As suggested by Douglas, if the mounted shared disappears or
is not present, OMERO will try to use the mount point instead.
Move shares section up
Fix .. note indentation
merge develop -D org -I include -E exclude: PR 293 (Add mount-point suggestion from Douglas Russell (Fix #9801) (rebased onto develop))
merge develop -D org -I include -E exclude: PR 295 (Fix .. note indentation (rebased onto develop))