dispatch: only do __import__(debugger) when a debugger is requested
When having ui.debugger=somedebugger in one's ~/.hgrc, this then
somedebugger would be imported for every hg command. With this patch,
this import only happens if the --debugger parameter is passed.
<?xml version="1.0" encoding="{encoding}"?>
<rss version="2.0">
<channel>
<link>{urlbase}{url|urlescape}</link>
<language>en-us</language>