Plugins affecting the CLI by default makes sense to me.

I'm less confident about them always affecting users of the Python API.

I'm going to have them apply by default, but I'm going to add a mechanism to opt-out on an individual database basis. Basically this:

from sqlite_utils import Database
db = Database(memory=True, execute_plugins=False)
# Anything using db from here on will not execute plugins

cc @asg017

Refs:

• Plugin system #567
• prepare_connection() plugin hook #574