[IMP] account: refactored the algorithm that returns a reconciliation proposition so it can be used to get a unambiguous proposition (for automatic reconciliation on statement import) and it can return a set of oldest move lines whose amount is <= to the line's amount
[FIX] account: removed the possibility to load reconciliation data without reconciliation proposition. It was useful to avoid that a statement line partner be replaced due to a structured communication match (which was stupid and is now fixed)
[REF] account: get_reconciliation proposition (to squash with 276c6e09ccd81f748be10cc5cec9788b7b638c31)
[IMP] account: bank statement import: prevent from importing file more than once, automatically reconcile transactions after import and add a notification of what was done during import when redirecting to bank reconciliation interface
[ADD] bank statement import: ~~pretty~~ icons (well icons anyway)