* [NOD-420] Delay blocks with valid timestamp (non-delayed) that point to a delayed block.
* [NOD-420] Mark block as requested when setting as delayed.
* [NOD-420] Merge master; Use dag.timeSource.AdjustedTime() instead of time.Now;
* [NOD-420] Return nil when not expecting an error
* [NOD-420] Initialise delyaed blocks mapping
* [NOD-420] Trigger delayed blocks processing every time we process a block.
* [NOD-420] Hold the read lock in processDelayedBlocks
* [NOD-420] Add delayed blocks heap sorted by their process time so we could process them in order.
* [NOD-420] Update debug log
* [NOD-420] Fix process blocks loop
* [NOD-420] Add comment
* [NOD-420] Log error message
* [NOD-420] Implement peek method for delayed block heap. extract delayed block processing to another function.
* [NOD-420] Trigger process delayed blocks only in process block
* [NOD-420] Move delayed block addition to process block
* [NOD-420] Use process block to make sure we fully process the delayed block and deal with orphans.
* [NOD-420] Unexport functions when not needed; Return isDelayed boolean from ProcessBlock instead of the delay duration
* [NOd-420] Remove redundant delayedBlocksLock
* [NOD-420] Resolve merge conflict; Return delay 0 instead of boolean
* [NOD-420] Do not treat delayed block as orphan
* [NOD-420] Make sure block is not processed if we have already sa delayed.
* [NOD-420] Process delayed block if parent is delayed to make sure it would not be treated as orphan.
* [NOD-420] Rename variable
* [NOD-420] Rename function. Move maxDelayOfParents to process.go
* [NOD-420] Fix typo
* [NOD-420] Handle errors from processDelayedBlocks properly
* [NOD-420] Return default values if err != nil from dag.addDelayedBlock
* [NOD-420] Return default values if err != nil from dag.addDelayedBlock in another place
Co-authored-by: Svarog <feanorr@gmail.com>