adopt actix-settings crate (#270)

* adopt actix-settings crate

* add licenses and readme addition

* revamp readme

* delete temp prettier file

actix-settings/README.md

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+# actix-settings
+
+> Easily manage Actix Web's settings from a TOML file and environment variables.
+
+[![crates.io](https://img.shields.io/crates/v/actix-settings?label=latest)](https://crates.io/crates/actix-settings)
+[![Documentation](https://docs.rs/actix-settings/badge.svg?version=0.5.2)](https://docs.rs/actix-settings/0.5.2)
+![Apache 2.0 or MIT licensed](https://img.shields.io/crates/l/actix-settings)
+[![Dependency Status](https://deps.rs/crate/actix-settings/0.5.2/status.svg)](https://deps.rs/crate/actix-settings/0.5.2)
+
+## Documentation & Resources
+
+- [API Documentation](https://docs.rs/actix-settings)
+- [Usage Example][usage]
+- Minimum Supported Rust Version (MSRV): 1.57
+
+### Custom Settings
+
+There is a way to extend the available settings. This can be used to combine the settings provided by Actix Web and those provided by application server built using `actix`.
+
+Have a look at [the usage example][usage] to see how.
+
+## WIP
+
+Configuration options for TLS set up are not yet implemented.
+
+## Special Thanks
+
+This crate was made possible by support from Accept B.V and [@jjpe].
+
+[usage]: https://github.com/actix/actix-extras/blob/master/actix-settings/examples/actix.rs
+[@jjpe]: https://github.com/jjpe