Feature Request: Backup

[gjrtimmer]

unqlite is considered to be the nosql counterpart of sqlite.
There are however some features available within sqlite which I also would like to see in unqlite.

Feature Request: Backup

Implementation of a backup method. This backup method will take a filepath as argument.
It will take the write lock on the unqlite file so all readers have to wait. Then it will copy the entire unqlite to the provided filepath, as a backup/snapshot.

This will allow to create a backup of a unqlite database without shutting down all connections to release the file.

[LeRatierBretonnien]

Good idea, and really useful against potential disk/file crash.