Procedures: switch to ".backup" function for SQLite DB backup
Procedures: switch to ".backup" function for SQLite DB backup

Instead of copying the database, we're now using a special ".backup"
SQLite client function designed for creating database copies.

swcarpentry/amy,pbanaszkiewicz/amy,pbanaszkiewicz/amy,swcarpentry/amy,pbanaszkiewicz/amy,swcarpentry/amy