Add ERC: Release tokens on predefined periods

[erc4377]

Tokens can be linearly released based on the predefined periods,enable lock token balances and gradually release tokens.

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[eip-review-bot]

File ERCS/erc-7660.md

Requires 1 more reviewers from @axic, @g11tech, @samwilsn, @xinbenlv

[SamWilsn]

Not sure if you're still working on this or if it's ready for re-review, but you will need to address the comments in the Rationale section before this can be merged.

[github-actions[bot]]

The commit 85d57e664cb7973b8730bdc130703262224dea35 (as a parent of 8338f56e80eb9116684f72d54ee8481496eccec1) contains errors. Please inspect the Run Summary for details.

[github-actions[bot]]

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[bot]]

This pull request was closed due to inactivity. If you are still pursuing it, feel free to reopen it and respond to any feedback or request a review in a comment.