Improve data docs

[akihironitta]

What does this PR do?

Description of the changes

• Adds Deserializer
• Includes minor fixes/improvements, e.g. links/formatting/...

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• [n/a] Did you make sure to update the documentation with your changes?
• [n/a] Did you write any new necessary tests? [not needed for typos/docs]
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[codecov]

Codecov Report

Merging #355 (aa3644d) into master (8077f7b) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #355   +/-   ##
=======================================
  Coverage   91.31%   91.31%           
=======================================
  Files         112      112           
  Lines        7127     7127           
=======================================
  Hits         6508     6508           
  Misses        619      619           

Flag	Coverage Δ
unittests	91.31% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
flash/core/data/process.py	86.34% <ø> (ø)

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[ethanwharris]

@akihironitta Great work here 😃 shall we merge this one so you don't get out of sync in #555?

[akihironitta]

@ethanwharris Sure, sounds good!