Squashed commit of the following:

What I did

• Implemented setting of the base model class, and populating data, at instantiation time.
• Implemented automated mapping of base model class based on DF_Model::$result_class

Implications

• The population of data currently uses a simplistic approach — should really use the table map. Will probably update this later.
• A single result class cannot be re-used between multiple models — otherwise Madness ensues.

Setup

None

How to test

• Code review.
• Test with commit e31a52d169b899a4ffc7892d3a5f030daae6c91e on Art Money
  • Note the changes in that commit.
  • Go to the admin screen for an active loan.
  • Add new payments to the bottom of the list.
  • Confirm that they save, and that the screen refreshes correctly.
• Ensure loading related records works as expected
• Try using this approach in another project.
• Try and break it!