Change the name of the default rake task

[chrismytton]

Problem

The rake task currently defaults to being called :test, but this conflicts with Rake::TestTask.

Proposed solution

Change the name of the rake task this library produces. I think calling it :scraper_test would probably be sensible.

[tmtmtmtm]

Maybe :test_data (or :data_test), to emphasise that it's running the data-driven tests?

[chrismytton]

Ah yep, I like :test_data. I think perhaps it would be more "standard" (FSVO) to call it test:data (with a : instead of an _)?

[tmtmtmtm]

Works for me!