* Adds sequence diagram for local download
* Adds network download flow
* makes node properly request block when presence-list is received
* starting to work :O
* Fixes fully connected download test up to 20 nodes.
* Better sequence diagram of network block resolution
* Cleans up comments and traces.
* Accidentally deleted important else
* Review comments by Dmitriy
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Co-authored-by: benbierens <thatbenbierens@gmail.com>
jessiebroke