Ability to import transactions via CSV more than once (edited)

Vince

The automatic connect & import capability is great but flaky (Fidelity, Vanguard, etc. always seem to have issues). When it's not working we're just stuck without the ability to import transactions. Extending the existing import capability beyond once would give us something to fall back. I can go to my bank and download transactions and import them into Simplifi. It's also useful for folks who don't want to enter bank account credentials into Simplifi for security reasons.