# Functions
Control is called after DNS lookup, but before the network connection is initiated.
NewDefaultClient creates a client with sane defaults.
NewDefaultClientWithTLS creates a tls client with sane defaults.
NewDefaultTransport creates a new transport with sane defaults.
NewDefaultTransportWithTLS creates a new transport with the specified TLS configuration.
# Variables
DefaultValidator is the default validator, it can be replaced at start time with a different validator.