Migrate to H2 version 2.1, Automate PostgreSQL build and test, Update Code Coverage

[JohT]

Changes

Migration to H2 version 2.1

As documented in https://github.com/quarkusio/quarkus/wiki/Migration-Guide-2.9 and more detailed in http://www.h2database.com/html/migration-to-v2.html there are some migration steps necessary to update H2 to its new major version 2.

• Rename database columns from "timestamp" to "eventtimestamp" to avoid conflicts with reserved words
• Use quotes for case-sensitive database schema names
• Document additional command line parameter "-ifNotExists" for local H2 database start
• Use upper-case column names for H2

Continuous Integration Workflow for PostgeSQL

• Add new workflow to build and test with PostgreSQL database based on Creating PostgreSQL service containers
• Use PhantomJS 2.1.1 that supports linux, since the new workflow runs within a linux docker container
• Provide configurable database hostname and port via environment variables to connect to docker PostgreSQL service instead of localhost.

Update Code Coverage for tests

• Update dependency org.jacoco:jacoco-maven-plugin to v0.8.8
• Change <phase>test</phase> to <phase>post-integration-test</phase> in pom.xml for jacoco-check execution, so that all tests are included as before and branch coverage limit is met