Improvements to DF_Model_result

What I did

• Implemented setting of the base model class, and populating data, at instantiation time.
• Implemented three options for choosing the base model class:
  • Specified at result object instantiation time
  • Configured in result class
  • Automatically derived from our model/result naming convention

Implications

• The population of data currently uses a simplistic approach — should really use the table map. Will probably update this later.
• Had to add the is_model_loaded() method to our loader subclass, as CodeIgniter doesn't supply this for models, and it proved resistant to other approaches.

Setup

None

How to test

• Code review.
• Test with commit b41cfaf344d6a68743e6d3e828bcd50ccf9510cf 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.
• Try using the other methods of setting the base model class, and add temporary debugging into _set_base_model() in DF_Model_result to confirm that those options are used and the tests still work.
• Try using this approach in another project.
• Try and break it!