Fix build setup to make artefact importable with maven/sbt
This release updates the build setup (i.e. the pom.xml and the publishing process) so that the artefacts published to maven can now be imported using maven or sbt. There are four branches associated with this new release:
- for spark 2.2: https://github.com/awslabs/deequ/tree/release/1.2.2-spark-2.2
- for spark 2.3: https://github.com/awslabs/deequ/tree/release/1.2.2-spark-2.3
- for spark 2.4: https://github.com/awslabs/deequ/tree/release/1.2.2-spark-2.4
- for spark 2.5: https://github.com/awslabs/deequ/tree/release/1.2.2-spark-2.5