Auto merge of #2638 - newpavlov:openssl, r=jtgeibel

Replace OpenSSL with RustCrypto crates

This project already has `sha2`, `sha-1` and `hmac` in its dependency tree (older versions for now), so I think it makes sense to use them directly instead of relying on OpenSSL. Plus it simplifies code a bit.

Note that this change does not remove indirect dependency on OpenSSL, since it's still used by `git2`, `libssh2` and `native-tls`.

Author: bors

Cargo.lock

@@ -37,7 +37,7 @@ url = "2.1"
 tar = "0.4.16"
 base64 = "0.12"
 
-openssl = "0.10.13"
+sha2 = "0.9"
 oauth2 = { version = "3.0.0", default-features = false, features = ["reqwest-010"] }
 log = "0.4"
 env_logger = "0.7"

Cargo.toml

@@ -16,5 +16,6 @@ path = "lib.rs"
 [dependencies]
 base64 = "0.12"
 chrono = "0.4"
-openssl = "0.10.13"
+sha-1 = "0.9"
+hmac = "0.8"
 reqwest = { version = "0.10", features = ["blocking"] }