Easy Digital Downloads - Commissions 3.5.2

• Fix: [edd_commissions] CSV export not respecting selected month and year parameters.
• Fix: Frontend Submissions - PayPal Email field no longer visible.

Fix: constants were not being defined early enough to be used in integrations.
Fix: Refunded payment notes included broken HTML.

Fix: Incorrect commission amount recorded for zero decimal currencies, which could result in confusing totals.
Fix: Deprecation notices in PHP 8.
Fix: Remove number formatting on CSV exports. (This caused problems when importing into PayPal Masspay.)
EDD 3.0: Update hook used for refund logic.