[gambit-list] Integrating Glass Table with the Gambit repl

All,

Kudos to Marc for showing us how to use `macro-repl-channel-read-command-set!' to alter how the REPL reads input. Based on this, the version of Glass Table now in GitHub[0] will integrate with the Gambit REPL, and should allow both Gambit and GT REPL commands to be used.

It was always a goal of mine with GT to build on Marc's concept that the REPL itself is an IDE; and to do so in a way that incorporates and extends the great ideas present in the Gambit REPL. This change moves GT a bit further along the path from "interesting hack" to serious development tool.

[0] https://github.com/bitwize/glasstable/