Added test for generation of while statement
Made class used for generating variable names more generic since it will be used when transforming the OO AST
Moved utility class used for generating variable names from JavaFormat to OoAstInfo since it is now used in transformations of the OO AST
Added generation of while statement
Made access to OoAstInfo through OoAstGenerator so that this information is available for additional transformations of the OO AST
Clean up of identifier designator
Added first step of generating sequence comprehensions. The remainding part will be done in an additional transformation of the OO AST. In addition a fix for generating variable expressions, when the variable has no owning class (such as x in [ x * 2 | x in set elems [1,2,3] & pick() ]).