Handle the optional table row end entirely in the lexer
Simplify WikiWords rule
Don't allow literal linebreaks in list items
Remove a needless variable
Render as blocks paragraphs of code/macros.

If a paragraph consists of just code or macros, separated by newlines,
then all of those elements are rendered as blocks - even though there is
no paragraph break between them. This is, again, going against the
WikiCreole standard, but is needed for backwards compatibility.