Handle newer compatibility modes without losing the ability to read the metadata
Indent.
Make inserts use COMPAT_1416 for now (** MUST REVERT IN 1467 **)
Change Metadata to keep topCompatibilityMode as a CompatibilityMode (unknown == 0 so same behaviour). May not be back compatible!
Check for COMPAT_CURRENT
Check for COMPAT_CURRENT here too
Use CompatibilityMode's in CompatibilityAnalyser and SplitfileCompatibilityModeEvent too. Might break serialization but shouldn't break downloads; non-splitfile downloads may restart. Inserts may break.
Accurately detect largish 1416 inserts (because of the bug)
Don't resume returnBucket, ClientGet will do it for us.
Explain CompatibilityMode, and delete obsolete comment.