Homepage: Updated Engine article; revised feature list
Homepage|Add-on Repository: Updated Add-on Repository; more semantic markup, styling
Homepage|Build Repository: Updated Build Repository; more semantic markup, styling
Homepage: Updated Games page; more semantic markup, styling
Homepage: Updated Decade of Doomsday page; more semantic markup, styling
Homepage: Updated platform and source pages; more semantic markup, styling
Homepage: Updated remaining pages/page elements; more semantic markup, styling
Homepage|Master Browser: Updated master server browser; more semantic markup, styling
Homepage: Revised page structure for new layout