* Avoid context canceled errors
Return 499 Client Closed Request when the client has closed the request before the server could send a response
Signed-off-by: Seena Fallah <seenafallah@gmail.com>
This reintroduces support for Go modules, as v4.
CloseNotifier() is removed as it has been obsoleted, see https://golang.org/doc/go1.11#net/http
It was already NOT working (not sending signals) as of 1.11 the functionality was gone, we merely
deleted the functions that exposed it. If anyone still relies on it they should migrate to using
`c.Request().Context().Done()` instead.
Closes#1268, #1255
