Merge branch '46-refactor-debug-messages-from-system-out-to-slf4j' into 'dev'

pages/docs/compiler.md

ragconnect.base/src/main/jastadd/Intermediate.jadd

ragconnect.base/src/main/jastadd/RagConnect.relast

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

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

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

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

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

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

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

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

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

ragconnect.tests/build.gradle

...t/java/org/jastadd/ragconnect/tests/AbstractMqttTest.java

...ts/src/test/java/org/jastadd/ragconnect/tests/Errors.java

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