fix a few directives using the old syntax

I'm turning on prefix_directives for the live wiki now.

doc/plugins/aggregate/discussion.mdwn

@@ -35,7 +35,7 @@ Two things aren't working as I'd expect:
 > problem. You can see the feed validator complain about it here:
 > <http://feedvalidator.org/check.cgi?url=http%3A%2F%2Fwww.davidj.org%2Frss.xml>
 > 
-> It's sorta unfortunate that [[cpan XML::Feed]] doesn't just assume the
+> It's sorta unfortunate that [[!cpan XML::Feed]] doesn't just assume the
 > un-esxaped html is part of the description field. Probably other feed
 > parsers are more lenient. --[[Joey]]
 

doc/tips/inside_dot_ikiwiki.mdwn

@@ -66,7 +66,7 @@ to do it rarely, and the data I've wanted has been different each time.
 
 ## the session database
 
-`.ikiwiki/sessions.db` is the session database. See the [[cpan CGI::Session]]
+`.ikiwiki/sessions.db` is the session database. See the [[!cpan CGI::Session]]
 documentation for more details.
 
 ## lockfiles

doc/todo/support_creole_markup.mdwn

@@ -12,7 +12,7 @@ And there is a perl module:   Text::WikiCreole
 
 Syntax file for vim: http://www.peter-hoffmann.com/code/vim/  (Since a typical ikiwiki user usually use external editors. :))
 
-> Should be pretty easy to add a plugin to do it using [[cpan
+> Should be pretty easy to add a plugin to do it using [[!cpan
 > Text::WikiCreole]]. --[[Joey]]
 
 [[done]]

doc/todo/syntax_highlighting.mdwn

@@ -7,16 +7,16 @@ pages, as well as doing syntax highlighting as a preprocessor directive
 
 ## The big list of possibilities
 
-* [[plugins/contrib/highlightcode]] uses [[cpan Syntax::Highlight::Engine::Kate]],
+* [[plugins/contrib/highlightcode]] uses [[!cpan Syntax::Highlight::Engine::Kate]],
   operates on whole source files only, has a few bugs (see
   [here](http://u32.net/Highlight_Code_Plugin/), and needs to be updated to
   support [[bugs/multiple_pages_with_same_name]].
-* [[cpan IkiWiki-Plugin-syntax]] only operates as a directive.
+* [[!cpan IkiWiki-Plugin-syntax]] only operates as a directive.
   Interestingly, it supports multiple highlighting backends, including Kate
   and Vim.
 * [[plugins/contrib/syntax]] only operates as a directive
   ([[not_on_source_code_files|automatic_use_of_syntax_plugin_on_source_code_files]]),
-  and uses [[cpan Text::VimColor]].
+  and uses [[!cpan Text::VimColor]].
 * [[plugins/contrib/sourcehighlight]] uses src-highlight, and operates on
   whole source files only. Needs to be updated to
   support [[bugs/multiple_pages_with_same_name]].
@@ -43,7 +43,7 @@ pages, as well as doing syntax highlighting as a preprocessor directive
   inside source files. Doing this probably means post-processing the 
   results of the highlighting engine, to find places where it's highlighted
   comments, and then running them through the ikiwiki rendering pipeline.
-  This seems fairly doable with [[cpan Syntax::Highlight::Engine::Kate]],
+  This seems fairly doable with [[!cpan Syntax::Highlight::Engine::Kate]],
   at least.
 * The whole-file plugins tend to have a problem that things that look like
   wikilinks in the source code get munged into links by ikiwiki, which can

doc/users/xma.mdwn

@@ -9,7 +9,7 @@ Anyway, [[ikiwiki]] is really *awesome* !
 
 ## More about me
 
-I am CLI user living in the linux console. More precisely, I live in an [[GNU Emacs]] frame all day long. My main computer is an EeePC 901 running Slackware GNU/Linux 12.1. I do not have X installed (too lazy) but when in X, I am running an instance of [[CLFSWM]].
+I am CLI user living in the linux console. More precisely, I live in an [[GNU_Emacs]] frame all day long. My main computer is an EeePC 901 running Slackware GNU/Linux 12.1. I do not have X installed (too lazy) but when in X, I am running an instance of [[CLFSWM]].
 
 ## Contacting me