Fixes unitialised variable warning and possible related bugs. Sets QDataStream::Qt_4_8 for better compatibility with older Qt versions
Improves the formula parser to accept parenthesis and + - * / and allow the formula to be any length. (NOT WORKING)
Fixes some bugs with the formula interpreter. Parenthesis still doesn't work with it so those bits are commented out.
Allows use of parenthesis in expressions but still does not work if expression starts with a bracket.