Carlos Garcia Campos authored Jul 04, 2019 and Carlos Garcia Campos committed Jul 31, 2019

Add new API to add WebSocket extensions to SoupSession and SoupServer
and include an implementation of permessage-deflate extension (see RFC
7692). In the client side, supported extensions are added to the session
as sub-features of a new session feature, SoupWebsocketExtensionManager.
In the client side, supported extensions are added/removed directly using
the new SoupServer API. All functions to negotiate the handshake
(client_prepare, client_verify, server_check and server_process) have
now a _with_extensions alternative to handle the extensions.