Use absolute path of config file.

This can provide better error messages in case the config file is not found.
Remove parametrization from function in favor of accessing globals.

I am not sure this is a good idea, but for now it helps simplifying the code.
Bring tests back to life.
Log SQLite version.

This is useful for debugging SQLite problems, such as running an old version without FTS4 support.
Update README.
Update serving log message