DIFFERENCE function now working properly. Still requires both tabs to have same # of rows for adding.
Merge https://github.com/cjmills30/Programmers-Union
PRODUCT function now works. Test using DBMS_program.cpp but function is now also in DBMS_combined.cpp, just need to implement parser to run function with keywords.
Merge https://github.com/cjmills30/Programmers-Union

Conflicts:
	DBMS.cpp
	DBMS_combined.cpp
Product is now working. SORRY if this shows up twice, but I hit commit and I don't see it online so trying again. I use DBMS_program.cpp to test the function. It's in DBMS_combined.cpp as well but the parser isn't setup with the function yet.