Divide tests to fast and slow

[petteripitkanen]

The search and filtering tests that are using the crop database take a long time, it would be nice to divide tests to fast and slow. Probably add another package.json script test-also-slow that would run all tests, add a tag to the slow tests and use the --grep option of Mocha. Or is it possible to filter tests by selecting those that have timeout set to high value or infinite?