[css3-multicol] typos in the spec

Hey everyone,

I think I found a few typos in the multicol spec at
http://www.w3.org/TR/css3-multicol/

Below are the relevant excerpts:

- In this example, *but* the number and widths of columns *is* set: → both /
are
- All column rules in the same row are also equal, if *the* appear; → they
- column *rows* only appear between columns that both have content. → gaps
- In actual implementations these *ares* will be determined by the
background. → areas

There are probably more; I didn't read the whole document closely, but I
thought I'd inform someone about these.

Cheers,
Waldir