send receipt from contrib/event/membership should list all configured FROM email addresses

currently, if you create a contribution/event/membership record from within the contact record, and you enable the option to send a receipt, the list of FROM addresses available includes:

• the contact's email addresses
• the primary/default domain address
• the address included in the event configuration

it should include ALL configured FROM addresses – not just the default. as it's not uncommon for organizations to have departmental email addresses (e.g. membership@), they should all be available in this context.