Lock down vault configuration file

[langston-barrett]

• Installs cleanly on a fresh build of most recent master branch
• Upgrades cleanly from the most recent release
• Updates documentation relevant to the changes

Fixes #1493

[langston-barrett]

The CI build is failing unrelatedly, this will need manual testing.

[langston-barrett]

This works for me on digitalocean:

$ ansible role=control --become -a 'ls -alh /etc/vault/vault.hcl'
lb-mi-control-01 | success | rc=0 >>
-rw------- 1 root root 334 Jun  1 17:32 /etc/vault/vault.hcl

lb-mi-control-02 | success | rc=0 >>
-rw------- 1 root root 334 Jun  1 17:32 /etc/vault/vault.hcl

lb-mi-control-03 | success | rc=0 >>
-rw------- 1 root root 334 Jun  1 17:32 /etc/vault/vault.hcl

deployed, and everything's healthy!

[langston-barrett]

rebased for automated testing on other clouds

[ChrisAubuchon]

👍