Ability to set import rules for similar transaction types

When importing, you can currently only set which columns correspond to which field in bulk. It would be useful to have an extra optional step that would allow the user to match specific payees from the file to payees that already exist in MoneyCoach or to designate it to create a new payee. The same for Accounts, Categories, Descriptions, Tags, etc.

This type of feature will become more helpful as automatic imports from external accounts is introduced, but it’d still be helpful to have for one-time imports, as well. Additionally being able to simply configure these import rules to recognize and remember matches for any future imports inside the settings somewhere would be helpful to reduce the need to repeatedly update the import rules each and every time an import runs (whether automatic or one-time).