Fix TFOBJ_TYPE_LIST memory leak

[davc0n]

Hi Salvatore,

Thank you very much for the C course :)

This small PR fixes a missing free call for TFOBJ_TYPE_LIST, elements are freed in the loop but the list itself is not (this is handled correctly in listPopType), and a crash in case of syntax error (compile method returns NULL, which in main was passed to printf).

Moreover changes the while loop of compile method to read the pointed value and not the pointer itself (which is never set to NULL and so the condition is always true), it is likely a typo (ref. lesson 2, minute 25).
The program worked anyway because of the break statement, which is still necessary because of parseSpaces, though someone learning might be confused seeing that while condition.