message: [Config Builder] Updated the Config Builder README with KeyManagerConfig and SecureBackendConfig information.
  Closes:
  Approved by: davidiw
diff: @@ -151,7 +151,7 @@ Similarly a public network could be added via:
  There are several different configurations contained within Libra Configuration.
  ### Libra Node Configuration
  -The Libra Configuration contains several modules:
  +The Libra Node configuration contains several modules:
  - AdmissionControlConfig - Where a Libra Node hosts their AC
  - BaseConfig - Specifies the Node's role and base directories
  @@ -160,7 +160,6 @@ The Libra Configuration contains several modules:
  system
  - ExecutionConfig - The gRPC service endpoint and path to the genesis file
  that defines the Move standard library and the initial Validator set.
  -- LoggerConfig - Configures the Libra logging service
  - MempoolConfig - Parameters for configuring uncommitted transaction storage
  - MetricsConfig - Local storage for metrics
  - NetworkConfig - LibraNet configuration file that specifies peers with keys,
  @@ -173,8 +172,17 @@ and other network configuration parameters
  set of peers that provide the data
  - StorageConfig - Where the LibraDB is stored and its gRPC service endpoints
  +### External Component Configurations
  +Outside of each Libra Node, external components can also be configured:
  +
  +- KeyManagerConfig - This contains configurations details for starting and
  +operating the Key Manager: the component service responsible for rotating
  +cryptographic keys for Libra Nodes.
  +
  ### Shared Configuration
  +- LoggerConfig - Configures the logging service for each component
  +- SecureBackendConfig - Configures the secure storage backend used by each component
  - TestConfig - Used during tests to hold account keys and temporary paths for
  the configurations that will automatically be cleaned up after the test.
  