tye secret store

[davidfowl]

For local dev passwords (sql server etc), we need a way to store local secrets and have the ochestrator to make them available to the process/container being launched. The main scenario for this is running local databases in tye. For example:

- name: vote
  project: vote/vote.csproj
- name: postgres
  image:  postgres
  env:
    - name: POSTGRES_PASSWORD
      value: "pass@word1"
  bindings:
    - port: 5432

It would be nice if that was a secret that could be referenced as such in the manifest and made available to the application.

- name: vote
  project: vote/vote.csproj
- name: postgres
  image:  postgres
  env:
    - name: POSTGRES_PASSWORD
      source: password
  bindings:
    - port: 5432