bump `hex` dependency (v0.3 to v0.4)

very little changed, compile fine after.

Cargo.lock

@@ -931,7 +931,7 @@ dependencies = [
 
 [[package]]
 name = "hex"
-version = "0.3.2"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -1274,7 +1274,7 @@ dependencies = [
  "env_logger 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "futures 0.1.29 (registry+https://github.com/rust-lang/crates.io-index)",
  "getopts 0.2.21 (registry+https://github.com/rust-lang/crates.io-index)",
- "hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hex 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.11.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "librespot-audio 0.1.3",
  "librespot-connect 0.1.3",
@@ -3271,7 +3271,7 @@ dependencies = [
 "checksum gstreamer-sys 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "fc1f154082d01af5718c5f8a8eb4f565a4ea5586ad8833a8fc2c2aa6844b601d"
 "checksum heck 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "20564e78d53d2bb135c343b3f47714a56af2061f1c928fdb541dc7b9fdd94205"
 "checksum hermit-abi 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)" = "3deed196b6e7f9e44a2ae8d94225d80302d81208b1bb673fd21fe634645c85a9"
-"checksum hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "805026a5d0141ffc30abb3be3173848ad46a1b1664fe632428479619a3644d77"
+"checksum hex 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "644f9158b2f133fd50f5fb3242878846d9eb792e445c893805ff0e3824006e35"
 "checksum hmac 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)" = "5dcb5e64cda4c23119ab41ba960d1e170a774c8e4b9d9e6a9bc18aabf5e59695"
 "checksum hostname 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3c731c3e10504cc8ed35cfe2f1db4c9274c3d35fa486e3b31df46f068ef3e867"
 "checksum httparse 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "cd179ae861f0c2e53da70d892f5f3029f9594be0c41dc5269cd371691b1dc2f9"

Cargo.toml

@@ -56,7 +56,7 @@ tokio-process = "0.2"
 tokio-signal = "0.2"
 url = "1.7"
 sha-1 = "0.8"
-hex = "0.3"
+hex = "0.4"
 
 [features]
 alsa-backend = ["librespot-playback/alsa-backend"]