cleared unused structures, modified prolog files

- updated ASTC.lhs ASTHaskell.lhs ASTInternal.lhs ASTJava.lhs
ASTLambdaProlog.lhs - cleaned up based on structures, operations, etc
that are not currently in use; also updated PrintC.lhs PrintHaskell.lhs
PrintJava.lhs PrintLambdaProlog.lhs ToHaskell.lhs ToC.lhs ToJava.lhs
ToLambdaProlog.lhs similarly.
- updated Helpers.lhs with additional Doc functions, etc.
- modified ideal solutions to better match internal implementation.
cleaned up unused files.
- modified internal implementations to suit all languages, including
lambda prolog now.
- put additional rough notes in reports to track progress for later
- updated Main (works now, creates new files in same directory
containing the generated code)
- for lambda prolog, "AST" "To" and "Print" files finally work now to
produce compilable code that produces the expected results
- updated let and assign expressions in ASTs and other files