working on functions for classes seemed to have started to wrok
Merge branch 'extensions' of https://gitlab.doc.ic.ac.uk/lab1314/wacc_37 into extensions
working on functions seemed to have started working needs checking
classes seem to be able to hold other classes and use their methods, even if their defined after, however if the class is defined after they cannot reference their fields
can now access fields defined in a later class as well as being able to reassign a class to something else
sorted semantic and backend to do with field references of later classes
remove bad add label
Arithmetic type equality needs checking.
Working on primitive type equality.