Item14333: Make it possible for plugins to disable SafeWikiPlugin

Useful for rest-calls. The plugins have to make insure the safeness of
the content themselves!

Ticket: #3533
Author:    Stephan Osthold <osthold@modell-aachen.de>
Date:      Wed Jan 22 14:33:44 2014 +0100

lib/Foswiki/Plugins/SafeWikiPlugin.pm

@@ -58,6 +58,7 @@ sub completePageHandler {
     #my($html, $httpHeaders) = @_;
 
     return unless $_[1] =~ m#^Content-type: text/html#mi;
+    return if Foswiki::Func::getContext()->{'OverrideSafeWikiPlugin'};
 
     # PDF generation fails if we filter it, so don't do that
     if ( exists $Foswiki::cfg{Plugins}{GenPDFPrincePlugin}{Enabled}