Improvements to payment entry

1) The Payment ID field should be pre-filled with, eg, “INV-1200”

2a) The date picker for payments seems to store a memory of previously entered dates, which is not only not useful, but also gets in the way of selecting the right date.

2b) The date picker for Created and Due Date also has buttons for Today, Clear and Close. Can you please change the payments date picker type to this one?