Bump strum from 0.19.5 to 0.20.0

Bumps [strum](https://github.com/Peternator7/strum) from 0.19.5 to 0.20.0.
- [Release notes](https://github.com/Peternator7/strum/releases)
- [Changelog](https://github.com/Peternator7/strum/blob/master/CHANGELOG.md)
- [Commits](https://github.com/Peternator7/strum/commits)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Cargo.lock

@@ -2008,7 +2008,7 @@ dependencies = [
  "rspotify",
  "serde",
  "serde_json",
- "strum 0.19.5",
+ "strum 0.20.0",
  "strum_macros 0.19.4",
  "tokio-core",
  "tokio-timer",
@@ -3269,9 +3269,9 @@ checksum = "4ca6e4730f517e041e547ffe23d29daab8de6b73af4b6ae2a002108169f5e7da"
 
 [[package]]
 name = "strum"
-version = "0.19.5"
+version = "0.20.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b89a286a7e3b5720b9a477b23253bc50debac207c8d21505f8e70b36792f11b5"
+checksum = "7318c509b5ba57f18533982607f24070a55d353e90d4cae30c467cdb2ad5ac5c"
 
 [[package]]
 name = "strum_macros"

Cargo.toml

@@ -42,7 +42,7 @@ rand = "0.7"
 webbrowser = "0.5"
 clipboard = { version = "0.5", optional = true }
 url = "1.7"
-strum = "0.19.5"
+strum = "0.20.0"
 strum_macros = "0.19.4"
 libc = "0.2"
 regex = "1"