Update Readme.md

[iesahin]

There are various leftovers from #2

• [x] Fix links in Thanks section

• [x] Add emoji to all sections

• [x] Fix codecov badge

• [x] Add badges for unsafe code, crates.io version and cargo installs like in https://github.com/rust-secure-code/cargo-geiger

• [x] Add badge for build status: https://shields.io/category/build

• [x] Add badge for downloads (crates.io and github) https://shields.io/category/downloads

• [x] Crates.io version tag: /crates/v/:crate

• [x] docs.rs version tag: /docsrs/:crate/:version?

• [x] Write a new section for Support

• [ ] Add a diagram for Quick Start section

[iesahin]

I think we can skip the diagram for now.