fix: expose TLS backend choice in features

Author: elsirion

.github/workflows/cont_integration.yml

@@ -24,6 +24,9 @@ jobs:
           - blocking
           - async
           - async-https
+          - async-https-native
+          - async-https-rustls
+          - async-https-rustls-manual-roots
     steps:
     - uses: actions/checkout@v3
     - name: Generate cache key

Cargo.toml

@@ -38,3 +38,6 @@ default = ["blocking", "async", "async-https"]
 blocking = ["ureq", "ureq/socks-proxy"]
 async = ["reqwest", "reqwest/socks"]
 async-https = ["async", "reqwest/default-tls"]
+async-https-native = ["async", "reqwest/native-tls"]
+async-https-rustls = ["async", "reqwest/rustls-tls"]
+async-https-rustls-manual-roots = ["async", "reqwest/rustls-tls-manual-roots"]

src/lib.rs

@@ -45,7 +45,15 @@
 //!
 //! * `blocking` enables [`ureq`], the blocking client with proxy and TLS (SSL) capabilities.
 //! * `async` enables [`reqwest`], the async client with proxy capabilities.
-//! * `async-https` enables [`reqwest`], the async client with support for proxying and TLS (SSL).
+//! * `async-https` enables [`reqwest`], the async client with support for proxying and TLS (SSL)
+//!   using the default [`reqwest`] TLS backend.
+//! * `async-https-native` enables [`reqwest`], the async client with support for proxying and TLS
+//!   (SSL) using the platform's native TLS backend (likely OpenSSL).
+//! * `async-https-rustls` enables [`reqwest`], the async client with support for proxying and TLS
+//!   (SSL) using the `rustls` TLS backend.
+//! * `async-https-rustls-manual-roots` enables [`reqwest`], the async client with support for
+//!   proxying and TLS (SSL) using the `rustls` TLS backend without using its the default root
+//!   certificates.
 //!
 //!