Cleanup: remove test_settings_module

[jayaddison]

Removes the test_settings_module, which is/was used mainly to enable suppression of exceptions during unit tests.

This uncovers a few exceptions that were occurring during the tests: mostly for cases where we had test coverage on fields for data that wasn't confirmed to be present on each page. Those are mostly removed.

[jayaddison]

Sorta makes me wonder whether removing ratings from the scraper template could make sense, if it's frequently unavailable. Or perhaps a comment to indicate that it's fine to remove/omit it that method's implementation when information is not present.

[bickerdyke]

A recipe does not necessarily need to be rated, so it shouldn't be a required field in a way that raises an exception when not available.

[jayaddison]

@bickerdyke hypothetical example: if recipe site http://example.org has recipes without ratings information, and we have a scraper called ExampleScaper to handle that site, what should calling .ratings() do for that scraper?

(currently it does raise an exception - not because the field is required, but because there's no implementation for it)