Add pending donations to admin donations index

And add more info to the details page

app/models/donation.rb

@@ -17,6 +17,7 @@ class Donation < ApplicationRecord
   scope :pending,    -> { where(payment_status: "pending") }
   scope :processing, -> { where(payment_status: "processing") }
   scope :completed,  -> { where(payment_status: "settled") }
+  scope :incomplete, -> { where.not(payment_status: "settled") }
 
   aasm column: :payment_status do
     state :pending, initial: true