Make UPLOAD_FROM into an enum
Move ReturnType to an enum too.
Move ReturnType to ClientGet
Move UploadFrom to ClientPutBase.
Remove some unnecessary code and imports from the migration code
Move persistence to an enum too
Persistence is always forever for migration code
Remove db4o cruft: Don't clone FreenetURI's
Fix using the wrong variable
Make Metadata document types an enum
Move splitfile algorithm to an enum
Fix resuming InsertContext splitfile algo's