Update README.md
Configured for PostgreSQL
Merge branch 'master' of https://github.com/boersmamarcel/challengesplatform

Conflicts:
	.gitignore
	Gemfile.lock
	config/database.yml
Merge branch 'master' of github.com:boersmamarcel/challengesplatform into develop

Conflicts:
	Gemfile.lock
	config/database.yml
Adds database.travis.yml