Fix and add SQL instructions

[anuveyatsu]

At the moment, we've removed SQL instructions on the showcase page as it is not working. We want to add it back once we found the source and have fully working one.

Acceptance criteria

• Working SQL instructions in the showcase page

Tasks

TODO

[Mikanebu]

I could not save data into SQL, since datahub urls are forbidden.

When I try to use method package.save('tesing.csv', storage='sql', engine=engine) from datapackage-py, it uses remote URL for resource to get the data that appears to be forbidden getting:

urllib.error.HTTPError: HTTP Error 403: Forbidden

However, if I use DataSet that lives on GitHub Eg: https://raw.githubusercontent.com/datasets/finance-vix/master/datapackage.json,
it works fine and saves data to sql.

@rufuspollock Any ideas why we are getting 403 forbidden from datahub?