Merge Kluug's Lazarus/FPC compatibility

It would be nice if you merge with your code Lazarus/FreePascal compatibility from Kluug's fork found here: http://www.kluug.net/omnixml.php. Lately I am looking only for components and libraries that work on both Delphi and Lazarus, and initially I didn't choose OmniXML just because it didn't work on Lazarus. Thanks to Kluug this isn't the case any more.