Update ERC-1363: Move motivation and rationale to eip1 recommendation

[vittominacori]

This PR is part of some changes I would like to make on ERC1363 to follow the modern EIP1 recommendation.

This PR:

• Update preamble and removed the not necessary simple summary section
• Refactor abstract section
• Moves the rationale from motivation into the rationale section

Note that this PR will not pass the CI, because of many changes required by validator and that are not addressed here but will be addressed in other PR.

I.g. external links, broken link, new line after h1, etc.

Other PR will address other sections of ERC1363

[eip-review-bot]

File ERCS/erc-1363.md

Requires 2 more reviewers from @axic, @gcolvin, @lightclient, @Pandapip1, @SamWilsn

[github-actions]

There has been no activity on this pull request for 2 weeks. It will be closed after 3 months of inactivity. If you would like to move this PR forward, please respond to any outstanding feedback or add a comment indicating that you have addressed all required feedback and are ready for a review.

[github-actions]

The commit 20ee1ff (as a parent of 41a72a1) contains errors.
Please inspect the Run Summary for details.

[SamWilsn]

These changes are a bit more involved than we allow for final EIPs. I think the best option would be to open a new EIP with the updated content.