Statement Object Events script; new property added to determine if the event is firing from a Calculation only

The Statement Object Events script fires when a Statement is required. This is used is two places:

1. When creating a Statement to send to the Account.
2. When calculating the future schedule for an Account, where a Minimum Payment must be found.

A new property, IsCalculationMode, has been added to finAccountStatement that determines if the event is fired as part of the Calculation to determine the Minimum Payment.

A second property, IsCalculationModeAndFirstNewStatement, has been added that returns True if it is the first new Statement to be generated in a Calculation. Note, this will include any backdated transactions prior to the beginning of the Statement period.

These flags can be used to optimise the script.