Add tests

[ocramz]

• Unit tests

• DB integration tests on Travis

  • see https://github.com/fpco/odbc/blob/master/.travis.yml

[gagandeepb]

About unit tests: how can I set up a replicable database environment so anyone cloning the repo is able to run the unit tests which will depend on a particular db name with certain table(s)/data in it ?

Similar question for Travis: is it possible to set up a database with a particular schema, filled with some mock data that Travis can use to run some tests against?

[gagandeepb]

Done. Integration tests added.