XML Report should be generated during site report generation if set to true

Here's the patch! I wasn't sure if we should check if .html was set to no and not do it, so I left that alone for now...

I have voluntarily not included the generation of the Clover xml report as a default (nor in the site goal). The reason is speed.

The xml report is not needed for the HTML generation and getting the xml report means running Clover twice. If you're not using the dashboard plugin, you don't need the xml report. What I could do (I've resisted it till now but we can include it if others think it's needed), is to define the clover xml report property by default inside the dashboard plugin.

I think it's actually a good idea or it'll soon become a FAQ...

Doing it now...

Done.

Hmm...the updated code only works if maven.dashboard.rungoals=true. However, I'm doing a multiproject:site, so I've got maven.dashboard.rungoals=false. Is this a misunderstanding on my part as to how to use this, or does this fix not quite address the problem?

Sean, if you do not let the dashboard run the goals, then it's of course up to you to generate the proper data needed by the aggregators. Thus you need to set the maven.clover.report.xml to true in your project. That sounds perfectly normal to me. Do you have any other better suggestion?

The problem isn't that I need to set maven.clover.report.xml to true...I'm already doing that. The problem is that the code ignores the fact that I've got it set to true and doesn't generate the XML report during site generation (even though it's set to true).