Compatibility Step 7

Another step towards running "Hunt the Wumpus" on Quite BASIC! :)

Today I added conditional GOTO to the language. I did it with mixed feelings because it is one ugly construct, but many early BASIC programs did use it.

So, now you can do things like:
10 LET R = 1 + RND(3)
20 ON R GOTO 100,200,300
...

That little code snippet will randomly make the program go to either line 100, 200, or 300.

Oh, and I also added the INT(x) function. It is the same as the existing FLOOR(x), but INT(x) is the name that classic BASIC programs used.