Add basic integer operations to lwcc Add +, -, *, and / to lwcc parser and code generator. Multiplication and division require helper functions in a yet to be created support library. These operations are integer only for the moment.

\.exe$
\.o$
\.d$
\.a$
~$
\.orig$
/lwbasic$
/lwlink$
/lwobjdump$
/lwar$
/lwasm$
/lwcc/lwcc$
/lwcc/lwcc-cpp$
/lwcc/lwcc-cc

# for windows
\.suo$
\.sdf$
\.opensdf$
\Debug$
\Release$