sqlite3-driver: rename prepare to prepare_db

[reynir]

In the same file there's another function called [prepare]. While the scopes do not overlap it can be a little confusing when using simple search in the file. I was reading the file and searching for the definition of prepare with simple search and I was surprised to see PRAGMA foreign_keys = ON was done each time.

[paurkedal]

Good point, though now that I'm aware of it, I wondering if it should be called something completely different like setup, or do we have a better name, to avoid the confusion with prepared statements.

[reynir]

I pushed a commit that changes it to setup. I can squash the commits if you like

[paurkedal]

Thanks, I think I can squash with the GitHub merge button.

[paurkedal]

Sorry I messed up the commit message a bit, but should be readable enough.