Accept message_id as param to write
Pull queued messages first, queue messages unless ID matches
Include message ID in event payload
Fix message_id in test
Extract queued_read(message_id) method
Extract message_queue accessor, documentation, cleanup
Clear search's message queue, instrument unread messages

Shouldn't have unread messages but provide a way to measure it anyway.
Merge pull request #138 from ruby-ldap/read-queue-by-message_id

Prioritize reads from queue by message ID