SKIP UPGRADE: Existing secret bug

Description

Per submitted bug - prior to this branch, users were unable to use existing secrets with this chart for the items that bigbang has added to this chart (./chart/tempaltes/bigbang/db/*)

This work allows the use of existing secrets for these jobs. The primary goal being backwards compatibility - as there are some more efficient ways to accomplish this task (but would break that compatibility).

Exceptions

This still requires the user to input the postgres values for endpoint/user - as the upstream uses these values in configmaps.

Issue

Package MR for #58 (closed)