Cash Flow Report

Currently implemented grapth shows aggregared (month, year) summ of transcation over selected account and counting only specific type (expenses, income, etc)

We missing classic Cash Flow Report. It shows ammount of actually accumulated funds over time (months, years). To make it simple it is like a monthtly snapshot of ammount of home page but historical. For parameters we should be able to select any accounts (as it is now for grapth) and any set of account type (multiselect, currently just one).

Grapth type is bar chart