Add support for libsql

[briancbarrow]

This should resolve issues connecting to a libsql database. Closes the issue I opened #192

All I did was copy the sqlite3store folder contents over into the new folder and updated the variables to ? instead of $1 etc.

Please let me know if any changes are needed.

[aranw]

Hey I was wondering whether there's any updates on getting this addition merged?

[briancbarrow]

@alexedwards I just wondered if you had a chance to look at this one yet? No pressure. I understand how busy life can get.