feat: add block archiving support

[a-saksena]

Story

AS A Block Node User
I WANT to have my block files archived
SO THAT I will have a reduced storage cost

Tech Notes:

• DEPENDS ON feat: add compression mode for BlockAsFileWriter #282

• See Design a directory structure #125 where we have defined the design of the new block-as-file.

• The scope of this issue is to add archiving support to the block files that will be written to disk.

• We need to implement a process/thread, that will be going to the fs and will be archiving block files that are already written to disk.

• The parameters of this process/thread should probably be configurable externally.

• The archiving process looks something like this:

  1. We zip the block files we need to zip.
  2. We rename the old folder (the one we just zipped) in order for new reads that have happened after we have zipped will go to the zip instead (they will be unable to find the file in it's original path).
  3. We remove the old folder (the one we renamed) after a bit of time, giving a chance to reads to finish reading, thus ensuring that readers will not be interrupted.