* Change request queue to slot queue
The request queue design was overly complicated as there was additional logic required to track one item with multiple slot indices. Instead, each item in the queue could be represented by a slot, and each time a request for storage is received, all slots for the request can be expanded and added to the queue.
* update note about resumption of queue processing
1. Add repair case — when a slot is freed in a contract
2. Clarify re-processing of requests
3. Format the document in sectional manner using Title, Heading 1, Heading 2
4. Organise the Request Queue design into sections
