Contract Chain Extension for Dapps-staking

[Maar-io]

Pull Request Summary

Introduce chain extension for Dapps-staking. With this extension any wasm contract will be able to communicate with pallet-dapps-staking

Check list

• [ ] contains breaking changes
• [ ] adds new feature
• [ ] modifies existing feature (bug fix or improvements)
• [ ] updated spec version
• [ ] relies on other tasks
• [ ] documentation changes
• [ ] tests and/or benchmarks are included
• [ ] changed API client type definition or chain metadata

This pull request makes the following changes:

Adds

• (ex: Add feature A)

Fixes

• (ex: Fix validation function)

Changes

• (ex: Change document B)

To-dos

*Feel free to remove this section if it's not applicable

• [ ] (ex: add user list)

[PierreOssun]

PR replaced by #729 Closing this one