Add token swap program

[dadamu]

Description

This PR registers token swap program to the parser manager, but it doesn't parse the whole structure for token swap messages since parsing all the messages for smart contract program is unnecessary now.

Checklist

• Targeted PR against correct branch.
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Wrote unit tests.
• Re-reviewed Files changed in the Github PR explorer.

[codecov-commenter]

Codecov Report

❗ No coverage uploaded for pull request base (master@bc5e77c). Click here to learn what that means.
The diff coverage is n/a.

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  Coverage          ?   61.06%           
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  Files             ?       24           
  Lines             ?      994           
  Branches          ?        0           
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  Hits              ?      607           
  Misses            ?      371           
  Partials          ?       16           

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[dadamu]

This PR is also a implementation of #75.