mapjfx 2.1.0 and 1.20.0 released, now built with JDK8 and JDK11

The new versions are 1.20.0 and 2.1.o, available in maven central:

  <dependency>
    <groupId>com.sothawo</groupId>
    <artifactId>mapjfx</artifactId>
    <version>1.20.0</version>
  </dependency>
  <dependency>
    <groupId>com.sothawo</groupId>
    <artifactId>mapjfx</artifactId>
    <version>2.1.0</version>
  </dependency>

Version 1.20.0 is built using OracleJDK8, whereas version 2.1.0 is built with OpenJDK11.