add experimental support for reals

src/main/java/de/tla2b/analysis/AbstractASTVisitor.java

src/main/java/de/tla2b/analysis/InstanceTransformation.java

src/main/java/de/tla2b/analysis/TypeChecker.java

src/main/java/de/tla2b/config/ModuleOverrider.java

src/main/java/de/tla2b/global/BBuildIns.java

src/main/java/de/tla2b/global/BBuiltInOPs.java

src/main/java/de/tla2b/global/TranslationGlobals.java

src/main/java/de/tla2b/output/TlaTypePrinter.java

src/main/java/de/tla2b/output/TypeVisitorInterface.java

src/main/java/de/tla2b/translation/OperationsFinder.java

src/main/java/de/tla2b/types/IType.java

src/main/java/de/tla2b/types/RealType.java

src/main/java/de/tla2bAst/BAstCreator.java