Core sampler: don't leave a DB connection out there flapping in the breeze

• main() now closes DB connection

approved this merge request

This change is really unnecessary. The database connection will be closed when the program exits—this is not a daemon process, just a quick binary.

it may be unnecessary, but it's good practice in general

This makes the code bigger but has no effect on how correct it is.

I'm with Janet here simply because I prefer explicit code. ¯\_(ツ)_/¯

It's your codebase. :)

merged