The EndpointConfig struct in the notifications package has some config
fields for a notification endpoint. This commit adds the ability to pass
in an *http.Transport to use when notifying that endpoint of an event.
This is especially useful for endpoints that use self-signed CAs.
Signed-off-by: Josh Chorlton <josh.chorlton@docker.com>
Since the notifications package is now decoupled from storage, we are moving it
to the root package.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
