[Documentation] Specify the default compiled sqlite extensions

[johnpyp]

Is your feature request related to a problem? Please describe.
Looking through the documentation, I couldn't find anything about which extensions were enabled during compilation by default.

For example, not all sqlite amalgamations in different languages choose to turn on the FTS5 extension, I wanted to know if it would work with this driver or not out of the box.

Describe the solution you'd like
Document the important sqlite extensions compiled here: https://github.com/xerial/sqlite-jdbc/blob/master/Makefile#L80-L104

If this was something thought about at some point, it would be nice to mention why or why not certain extensions get enabled, and what the criteria for a new one to get added would be. For example, would this project ever consider adding community sqlite extensions? I'd guess not, but it's not super clear.

Describe alternatives you've considered
Having users read through the code and find the Makefile... not great.

Additional context
N/A

[gotson]

PRs are welcome :-)