I removed the unecessary plugins from the build and reworked it to use
the ci friendly way of setting the version for releases (see
https://maven.apache.org/maven-ci-friendly.html).

This removes the spring-boot-starter-parent from the build, and
duplicates the necessary plugin configuration in he Spring Boot Admin'
parent instead. This way our BOM doesn't include version for
dependencies managed by boot's BOM

closes #299

The 1.4.0 release was a total disaster. Webpack didn't build the css correctly
because of travis using an ancient nodejs version.

fixes #205

I did an accidental release of a 1.3.2, so we need another increment

Remove unecessary dependencies

increment version