More descriptive / path handler

[Bostwickenator]

Instead of simply returning HTTP 404 Not Found for the default path I would like to return something slightly more informative. I suggest something along the lines of "This is a deps.cloud gateway server, please visit https://deps.cloud/ for usage instructions"

Implementation would go here:

depscloud/services/gateway/main.go

Line 160 in 93f9163

serverConfig.Endpoints = []mux.ServerEndpoint{

[mjpitz]

someone suggested having the swagger explorer as part of the root