trivial-sockets 0.4

This is a maintenance release of the legacy trivial-sockets package with all patches/issues mentioned on Cliki [1] merged/fixed. Changes:

• Fixed long-standing bugs in which 4-chars hostname lile "abcd" were wrongly recognized as IPv4 numeric addresses
• [cmucl] added UDP support (patch from Cliki)
• [cmucl] allow buffering choice in accept-connection (patch from Cliki)
• [mcl] added support of digital MCL (patch from Cliki, author: Lennart Staflin)

[1] https://www.cliki.net/trivial-sockets