Updated expected test results for many tests since new transformations will be introduced
Minor improvements for the generated code in the results files
Removed unused methods in the statement assistent
The default fallback case is not needed anymore now that functions can exist in the IR. In addition, some improvements for the handling of the return statement
Fix for the construction of the let def expression in the IR. The type was never set.
Added functions to the IR and made the necessary updates to an IR class. In relation to that, a "not implemented" expression has also been added to the IR.
Updated the IR visitors that construct the IR to take function declarations into account.
Added template for the "not implemented expression".
Added transformation for the let def expression
Added transformation for the if expression
Added transformation to transform functions into operations
Updated the Java code generator to use the newly introduced transformations