Easy Digital Downloads - Recurring Payments 2.12.3

• Fix: Corrected an issue in the subscriptions table that caused some subscriptions to be skipped in the last upgrade routine. Please run the new upgrade routine to ensure all price IDs are assigned correctly.
• Dev: Added a new generic hook for Stripe events: `edd_pre_recurring_stripe_event`

• Fix: If a product was deleted, it could cause subscription lists and emails to fail.
• Fix: Updated .pot file for translators.
• Fix: Stripe - Subscriptions were failing to be created on new purchases with Quarterly or Semi-Year periods.

Fix: Recurring tax recorded on renewal payments was incorrectly calculated.
Fix: Tax on renewal payments after an upgrade was not properly calculated.
Fix: Stripe failed upgrade attempts were causing duplicate subscriptions.
Fix: Warning due to checking for trials on checkout.
Fix: Prevent errors happening upon renewal emails in edge-case situations where no product is attached to a subscription.
Fix: Added defensive checking for errors in the response from PayPal Express.