NFT Sample Implementation

[okwme]

Work by @fedekunze and @okwme on a NFT module!

• Linked to github-issue with discussion and accepted design OR link to spec that describes this work.
• Wrote tests
• Updated relevant documentation (docs/)
• Added a relevant changelog entry: sdkch add [section] [stanza] [message]
• rereviewed Files changed in the github PR explorer

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For Admin Use:

• Added appropriate labels to PR (ex. wip, ready-for-review, docs)
• Reviewers Assigned
• Squashed all commits, uses message "Merge pull request #XYZ: [title]" (coding standards)

[codecov]

Codecov Report

Merging #4118 into develop will decrease coverage by 1.74%.
The diff coverage is 7.57%.

@@             Coverage Diff             @@
##           develop    #4118      +/-   ##
===========================================
- Coverage    59.98%   58.23%   -1.75%     
===========================================
  Files          211      221      +10     
  Lines        15131    15626     +495     
===========================================
+ Hits          9076     9100      +24     
- Misses        5433     5901     +468     
- Partials       622      625       +3

[rigelrozanski]

This PR needs to be reopened to Master branch