boilerplate code for tests
made database.py module reusable, it can now be used to connect to any datasource from anywhere
database.py manages db connection and session only, completely isolated
renamed api_tests.py to just tests.py
small bug, some insert and delete operations still referred to session.add instead of db.add
name 'id' was not defined
tests for all methods implemented for the /scorecards endpoint
modified helper function http_code so it handles all HTTP codes with no body
removed test_get_created_200 and test_get_deleted_404 (made no sense)
moved API calls to factories.js
api calls are now async (using promises) closes #12
variable indicator_id in PUT /scorecards was unexpected
don't leave period at the end of lines, added PUT method to factories.js and controllers.js
send available indicators and assigned indicators as a property of the scorecard object
closes #13
Merge pull request #18 from romeroqj/Issue_#13

Issue #13
merging pull request #15