Implement HashiCorp Vault Controller Service Configuration Properties

Hashicorp Vault controller service

Dynamic property descriptors - key (component PD identifier) / value (Vault identifier/location)

Components can reference controller service to populate property descriptors directly

Scenarios:

1. NiFi config values are stored in Vault & accessed via HVSPP

2. NiFi flow details are stored in Vault & accessed via HVCS; config values are not

3. Both are stored in Vault & accessed with HVSPP & HVCS

1. Refactor common code out of the HVSPP to "VaultCommunicationService" (framework level)

2. HVSPP delegates/wraps HVCommSvc (framework level)

3. HVCS delegates/wraps HVCommSvc (extension level)