FR: provide a way to 'suspend' Recurring Invoices rather than 'cancel'

[amjessey]

Feature Request: provide a way to 'suspend' a Recurring Invoices series rather than 'cancel' so we can resume the series whenever we want and pick up where we left off.

Currently, this feature is missing and we have to recreate the series each time which is a problem because it takes up time that could be saved. We also don't have complete oversight as broken series belonging to a customer are unconnected.