[Lazarus] FPDoc now with Markdown support

[Соболь Андрей Евгеньевич]

> I've been looking at allowing markdown for the description files (they would
> be less verbose then), but there seems to be no decent markdown parser available 
> for pascal. If somone cares to contribute one...

For "overview pages" (unit, class, package) I think need to move a "description section" to up and set it above a "uses section", because "description" is more useful information than list of units. Especially for the case when the list of files is big. I think that need to do for a html version also.