Build does not work on JDK 17

[duponter]

When building YAVI using Maven, I encounter following issues:

1. The build fails when using JDK 17. It does build using JDK 11. I haven't tested with other JDKs.
   This is caused by the ConstraintMetaProcessorTest that fails because of the following issue: Access to compiler internal APIs will fail starting with JDK 16 google/compile-testing#222.

Adding a Maven profile that activates on JDK 9+ and opens up access to the com.sun.tools.javac.api in jdk.compiler module solves this.

2. A warning is issued that the build is platform dependent:

[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!

Added 2 Maven properties settings encoding to UTF-8 fixes this.

3. Several warnings of missing plugin versions are shown.

[WARNING]
[WARNING] Some problems were encountered while building the effective model for am.ik.yavi:yavi:jar:0.9.0-SNAPSHOT
[WARNING] 'build.plugins.plugin.version' for com.mycila.maven-license-plugin:maven-license-plugin is missing. @ line 192, column 21
[WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-compiler-plugin is missing. @ line 152, column 21
[WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-jar-plugin is missing. @ line 227, column 21
[WARNING] 'build.plugins.plugin.version' for org.jacoco:jacoco-maven-plugin is missing. @ line 188, column 21
[WARNING]
[WARNING] It is highly recommended to fix these problems because they threaten the stability of your build.
[WARNING]
[WARNING] For this reason, future Maven versions might no longer support building such malformed projects.
[WARNING]

After adding the missing plugin versions, the warnings also disappear.

4. com.mycila.maven-license-plugin:maven-license-plugin is moved to com.mycila:license-maven-plugin.
   Old plugin: https://mvnrepository.com/artifact/com.mycila.maven-license-plugin/maven-license-plugin
   New plugin: https://mvnrepository.com/artifact/com.mycila/license-maven-plugin

Moving to the new Maven coordinates also upgrades this plugin to version 4.1.

[making]

Fixed via gh-177