Scandirectory follow symlinks

[oholiab]

This enables the use of symlinked files and directories in config directories:

root@46597d0d80f5:/work/linktest# ls
root@46597d0d80f5:/work/linktest# mkdir conf.d
root@46597d0d80f5:/work/linktest# mkdir linksources
root@46597d0d80f5:/work/linktest# cat > conf.d/unlinked-policy.hcl
environment "all" {
        policy "unlinked-policy" {
                path "blah" {
                        capabilities = ["read"]
                }
        }
}
root@46597d0d80f5:/work/linktest# cat > linksources/linked-policy.hcl
environment "all" {
        policy "linked-policy" {
                path "bleh" {
                        capabilities = ["read"]
                }
        }
}
root@46597d0d80f5:/work/linktest/conf.d# cat > /abslinked-policy.hcl
environment "all" {
        policy "abslinked-policy" {
                path "bler" {
                        capabilities = ["read"]
                }
        }
}
root@46597d0d80f5:/work/linktest# cd conf.d/
root@46597d0d80f5:/work/linktest/conf.d# ln -s ../linksources/linked-policy.hcl
root@46597d0d80f5:/work/linktest/conf.d# ln -s /abslinked-policy.hcl
root@46597d0d80f5:/work/linktest/conf.d# cd ..
root@46597d0d80f5:/work/linktest# ls -l conf.d/
total 4
lrwxrwxrwx 1 root root  21 Dec 18 16:18 abslinked-policy.hcl -> /abslinked-policy.hcl
lrwxrwxrwx 1 root root  32 Dec 18 16:10 linked-policy.hcl -> ../linksources/linked-policy.hcl
-rw-r--r-- 1 root root 163 Dec 18 16:00 unlinked-policy.hcl

# Current version without symlink fix, only deployes the unlinked policy
root@46597d0d80f5:/work/linktest# hashi-helper --environment all --config-dir conf.d/ vault-push-all
INFO[0000] Writing policy unlinked-policy

# This patch, pushes all of them
root@46597d0d80f5:/work/linktest# ../hashi-helper --environment all --config-dir conf.d/ vault-push-all
INFO[0000] Writing policy abslinked-policy
INFO[0000] Writing policy linked-policy
INFO[0000] Writing policy unlinked-policy
root@46597d0d80f5:/work/linktest#

If we could get a new minor version release on merge that would really help me out with getting it deployed :)