A few suggestions for tasks
 * Optimise
 * Refactor
 * Preprocessor
   - expand macros (under work)
   - include files
   - etc?
 * Token list
   - improve the variable id for class member variables
   - simplify "void f(x) int x; {" into "void f(int x) {"
   - etc?
 * Add unit tests
 * improved error message handling