!WikiWord suppression syntax should be eliminated, leaving the bare words
which will not be linked. The WikiWord is an annoying legacy from the original
wiki concept that has been needlessly perpetuated: a "neat" and lazy trick to
name and link new pages.

 !DefTerm:: !DefItem

{{{#!C
/* Some C source code. */

if (!finished)
    break;

if (!SomeOtherCondition)
    return;
}}}

Here, the !finished term should not be modified. The !SomeOtherCondition term
should not be modified in the region, but it may be modified here. So, one
might wish to use <<<!SomeOtherCondition>>> to protect it. Alternatively,
!WikiWord recognition might be suppressed using the appropriate option.
Constructs like this!thing should not even be matched.
