Allow docName="" for SSKs. GenerateSSK returns such pseudo-SSKs; we should allow them to be consistent. Also clients use them sometimes. Note that we recommend you not actually use this and put a site under it, e.g. SSK@blah,blah,blah//filename as it may confuse clients etc.
Document.
Fix bug #6088: Make migratePluginStores() not break startup on database corruption. Argh!
Build 1457

See tag for changelog.