Make rust-tls work (through ring)

crates/bencode/Cargo.toml

@@ -9,6 +9,10 @@ repository = "https://github.com/ikatson/rqbit"
 readme = "README.md"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+[features]
+default = ["sha1-crypto-hash"]
+sha1-crypto-hash = ["sha1w/sha1-crypto-hash"]
+sha1-ring = ["sha1w/sha1-ring"]
 
 [dependencies]
 serde = { version = "1", features = ["derive"] }