Add continuous build / testing of database

[rngadam]

Heroku CI would probably be best:

https://devcenter.heroku.com/articles/heroku-ci#configuration-using-app-json

steps

• create app.json
• allocate postgresql addon
• run setup script against database above
• run test script against database above
• parse TAP test results - follow up in issue Parse TAP results from pgtap #39
• autodeploy master on successful build

pgtap and heroku

pgtap unsupported right now on Heroku so have to come up with a different test

filed a support request

workaround: use vendored postgresql and install pgtap in every run.

see: heroku/heroku-buildpack-ci-postgresql#15