Gobierto Data / Integration tests

[ferblape]

Let's start adding Rails integration tests in data module. For simplicity we'll use Capybara to check all the user scenarios we want to cover.

For the moment we should have at least this:

• As a user, I visit a dataset and execute a query
• As a user, I visit a dataset and execute an invalid query
• As a user, I visit a dataset and execute a query and then another query
• As a user, I visit a dataset and execute a query that doesn't result results
• As a user, I visit a dataset and download data in JSON format
• As a user, I visit a dataset and download data in CSV format
• As a user, I visit a dataset, create a query and save it
• As a user, I visit a dataset, create a query and save it, then I update it and save it
• As a user, I visit a dataset and load an exising query
• As a user, I visit a dataset, I delete a query
• As a user, I filter datasets in the sidebar, visit a dataset and execute a query
  ....

Once these tests are setup I'd like we keep creating them as part as the development process