More detailed error message in case of command parse error (#684)

* Refactored `command::parse`

* Removed unnecessary duplication in error msg

* Renamed `NotEnoughArgs` -> `InsufficientArgs`

* Inaccurate var name

* Ditch wordy error prefix

* Use `split_whitespace` instead of regex

* Cleanup unused regex import

* `insert` cmd fails fast

* Refactor: use `and_then` instead of `unwrap`

* Updated `Command::to_string`

* Added `Command::basename`

* Better err msg when running cmd in unsupported view, fully closes #597

* Sort `match` branches by their order in the enum

src/spotify.rs

@@ -358,7 +358,7 @@ impl Spotify {
     }
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Copy, Clone, Serialize, Deserialize, Debug, PartialEq)]
 pub enum UriType {
     Album,
     Artist,