[phpwiki] Edit square brackets

This is a minor change, don't archive old version.
I can't type tabs. Please ConvertSpacesToTabs for me when I save.

GoodStyle tips for editing.
EditLinks to other web servers.

Emphasis: '' for italics, ''' for bold, ''''' for both
Lists: tab-* for bullet lists, tab-# for numbered lists, tab-Term:-tab for definition lists
References: JoinCapitalizedWords or use square brackets for a [page link] or URL [http://cool.wiki.int/].
References: Use [1],[2],[3],... and EditLinks. Avoid linking with "!": !DoNotHyperlink, name links like [text | URL]
Misc:"!", "!!", "!!!" make headings, "%%%" makes a linebreak, "- - - -" makes a horizontal rule, escape "[" with "[["
more on TextFormattingRules