8.0 fixes and improvements in bank statement reconciliation widget

- use move line name instead of move name if line name != '/'
- really select only one line from each partial reconciliation (correct excluded_ids)
- take into account that amount_residual can be < 0
- allow to change statement name from reconciliation widget
- make it harder to delete a statement line's partner
- better (re)loading animations
- allow to close multiple statements at once when reconciliation is finished
- allow to return to the bank statements tree view (but only return since it uses the action manager's breadcrumbs)
- fix a bug where the partial reconciliation icon didn't appear/disappear when it should have
i don't get what's the difference between 
1) total_amount_str and amount_str
2) total_amount_currency_str and amount_currency_str