lib/streams: Added class NetworkStream, for any kind of full-duplex network connection

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/socket: Adapted Socket class to NetworkStream

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/socket: Use more explicit names for Socket constructors.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/socket: Bugfix, when reading a message of length 0, consider the socket closed.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/websocket: Websocket subclass of NetworkStream.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/streams: stdin/out/err are now part of Sys and can be changed in subclasses if necessary.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
debugger: Unified services of streams under nit, removal of debugger_commons, nitdbg_server and websocket_server.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
debugger/client: Adapted and simplified code for the new version of server.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>