Analytic tags in account reconciliation

This module brings analytic tags into the bank reconciliation screen and into reconciliation models.

• On a bank statement line, a new "Analytic Tags" field appears in the manual reconciliation tab, right after the analytic distribution field. It is only shown to users who belong to the analytic tags group, is hidden for liquidity lines or when no manual account is selected, and becomes read-only once the line is reconciled.
• When you reconcile a statement line manually, the tags you picked are copied onto the journal item that is created, so the resulting accounting entry keeps the analytic tagging.
• The same tags are remembered when you switch between lines in the reconciliation widget: if you change the tags, the line is flagged as changed, and clearing the reconciliation also clears the tags.
• On reconciliation models, each model line now has an "Analytic Tags" column (hidden by default, can be shown). Tags set there are automatically applied to the write-off journal item generated by that model.
• The module touches account.bank.statement.line, account.reconcile.abstract and account.reconcile.model.line, and adds fields to the bank statement line reconciliation form and the reconciliation model form.