Fixed: single-batch writes and deletes are written as IsCommitted, ReadIndex rebuilding works with IsCommitted.
Added: $all reading knows about IsCommitted now.
ReadIndex refactoring, Prepare+Commit handling improved. Still work in progress...
Changed: use in memory cached of committed events when checking idempotency with explicit expected version.
Changed: moved actual committing to chaser.
Changed: removed ugly hack with catch-up subscription waiting for some events to appear in ES.
Reverted: changes in catch-up subscription to allow new client API to work with older ES.
Added: writer internal stream versions state reset for safety.