refactor: Rework to be proper abstraction of a SecretStore and add SecretStoreClient from edgex-go#91

Merged

lenny-goodell merged 5 commits intoedgexfoundry:masterfrom lenny-goodell:management-client

Feb 19, 2021

Commits on Feb 18, 2021

refactor: Refactor to be proper abstraction of a SecretStore
lenny
committed

Commits on Feb 19, 2021

refactor: Fixup from PR feedback
lenny
committed
refactor: More rework form PR review.
lenny
committed
refactor: Chnage unseal to just take KeysBase64
lenny
committed
refactor: Updated unit tests per PR discussion
lenny
committed