BFT Block Puller: expose BlockCensorshipTimeout in config

[tock-ibm]

File core/deliverservice/config.go defines configuration variables that are used in the CFT and BFT delivery clients.
We should add to that a

• BlockCensorshipTimeout that is used in the BFT deliverer.
• MinimalReconnectInterval (now is a baked in number 100ms

// DeliverServiceConfig is the struct that defines the deliverservice configuration.
type DeliverServiceConfig struct {
	// PeerTLSEnabled enables/disables Peer TLS.
	PeerTLSEnabled bool
	// BlockGossipEnabled enables block forwarding via gossip
	BlockGossipEnabled bool
	// ReConnectBackoffThreshold sets the delivery service maximal delay between consecutive retries.
	ReConnectBackoffThreshold time.Duration
	// ReconnectTotalTimeThreshold sets the total time the delivery service may spend in reconnection attempts
	// until its retry logic gives up and returns an error.
	ReconnectTotalTimeThreshold time.Duration
	// ConnectionTimeout sets the delivery service <-> ordering service node connection timeout
	ConnectionTimeout time.Duration
	// Keepalive option for deliveryservice
	KeepaliveOptions comm.KeepaliveOptions
	// SecOpts provides the TLS info for connections
	SecOpts comm.SecureOptions

	// OrdererEndpointOverrides is a map of orderer addresses which should be
	// re-mapped to a different orderer endpoint.
	OrdererEndpointOverrides map[string]*orderers.Endpoint
}

Update also the peer yaml files that are loaded from the file system on startup, and set reasonable defaults if these values are not found.

[tock-ibm]

See func (d *deliverServiceImpl) createBlockDelivererBFT in PR #4373