hmac: use release versions of dev-dependencies (#260)

Release PRs:
- `sha1`: RustCrypto/hashes#810
- others: RustCrypto/hashes#812

Author: tarcieri

Cargo.lock

@@ -17,10 +17,10 @@ digest = { version = "0.11.2", features = ["mac"] }
 
 [dev-dependencies]
 digest = { version = "0.11.2", features = ["dev"] }
-md-5 = { version = "0.11.0-rc.5", default-features = false }
-sha1 = { version = "0.11.0-rc.5", default-features = false }
+md-5 = { version = "0.11", default-features = false }
+sha1 = { version = "0.11", default-features = false }
 sha2 = { version = "0.11", default-features = false }
-streebog = { version = "0.11.0-rc.5", default-features = false }
+streebog = { version = "0.11", default-features = false }
 hex-literal = "1"
 
 [features]