Use a random DB password, to fix https://github.com/Automattic/vip-quickstart/issues/126
Revert "Use a random DB password, to fix https://github.com/Automattic/vip-quickstart/issues/126"

This reverts commit 9451ee193428b391ade5cb8d4e66485f3e0674a5.
Revert "Revert "Use a random DB password, to fix https://github.com/Automattic/vip-quickstart/issues/126""

This reverts commit 38e10cd0e0d13c9605b56e1b390ec4ffe2ccc0c6.
Remove extra lines
Replace the old DB password when we update it.

When you reprovision, a new password is generated. We need to
replace it in wp-config instead of adding another entry.

See #307
Merge branch 'ChrisHardie-master'

See #307