Imported GNAT.Sockets extras from <https://bitbucket.org/sparre/gnat-sockets-extras>.
Updated version of GNAT.Sockets Extras.
Ignore Mercurial repository data for GNAT.Sockets Extras.
Include the POSIX (FLORIST) and GNAT.Sockets Extras packages in the project.
Testing GNAT.Sockets, GNAT.Sockets Extras and POSIX.IO for a simple echo server.
Demonstrating a bug in GNAT-4.6 (Debian) and GNAT-GPL-2013.