WL#5288: Python support library in server

In order to support other uses of Lua within the server, it is necessary to add
support code to load the Lua implementation into the server for other plugins to
use.

The goal of this worklog is to implement the necessary thunks so that Lua can be
loaded dynamically into the server.

References
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WL#820 External language stored procedures

dev-public thread "Dreaming: lua as stored proc language"
https://intranet.mysql.com/secure/mailarchive/mail.php?folder=5&mail=69562