docs: replace the block description list with references

[agorararmard]

Match the listing in the Block Description subsection with the listing in the original source, and use references to the sections instead of using an auto generated table of contents.

• Tests pass
• Appropriate changes to README are included in PR

[google-cla]

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[agorararmard]

@googlebot I signed it!

[mithro]

This is replaced by #260