Updated initial version of Java handler.

.gitlab-ci.yml

ragconnect.base/src/main/jastadd/Handlers.jrag

...c/main/java/org/jastadd/ragconnect/compiler/Compiler.java

ragconnect.base/src/main/resources/JavaHandler.mustache

ragconnect.base/src/main/resources/handler.mustache

...onnect.base/src/main/resources/receiveDefinition.mustache

ragconnect.base/src/main/resources/sendDefinition.mustache

ragconnect.tests/build.gradle

ragconnect.tests/src/test/01-input/java/README.md

ragconnect.tests/src/test/01-input/java/Test.connect

ragconnect.tests/src/test/01-input/java/Test.jadd

ragconnect.tests/src/test/01-input/java/Test.relast

.../src/test/java/org/jastadd/ragconnect/tests/JavaTest.java