Re-export spnego feature from curl-sys (#313)

Fixes #300.

Author: sagebind

.github/workflows/main.yml

@@ -127,6 +127,8 @@ jobs:
           submodules: true
       - name: Install Rust
         run: rustup update stable && rustup default stable
+      - name: Install dependencies
+        run: sudo apt install libkrb5-dev
       - name: Build documentation
         run: cargo doc --no-deps --all-features
       - name: Publish documentation

Cargo.toml

@@ -40,6 +40,7 @@ default = ["ssl"]
 ssl = ["openssl-sys", "openssl-probe", "curl-sys/ssl"] # OpenSSL/system TLS backend
 mesalink = ["curl-sys/mesalink"] # MesaLink TLS backend
 http2 = ["curl-sys/http2"]
+spnego = ["curl-sys/spnego"]
 static-curl = ["curl-sys/static-curl"]
 static-ssl = ["curl-sys/static-ssl"]
 force-system-lib-on-osx = ['curl-sys/force-system-lib-on-osx']