Source code checked in, #71003

* Added ModerateComments option to Blog * Refactored Comments related code * Verified and added checks to Blog Post Publishing Code related to Date Folder structure * Replaced strings with relevant class DocumentTypeName fields as appropriate; made same fields static. * Re-Implemented XmlComments and XmlTrackbacks to return more than one comment/trackback (experimental - needs testing) * Lots of other small bug fixes