fix mpris metadata returing Spotify URI instead of an url in xesam:url field (#222)

* Added OpenUri D-BUS MPRIS support.
Removed "user:" from URIType check because Spotify doesn't always provide it.

* Added tags to .gitignore

* Changed mpris metadata to actually return the track's url instead of the Spotify URI so that it matches the functionality of the official Spotify client.

* Changed mpris:trackid and xesam:url to not use static naming so it can support podcasts.

* Changed xesam:url to default to an empty string instead of "0"

.gitignore

@@ -7,3 +7,5 @@
 **/*.rs.bk
 
 *.log
+
+tags

src/mpris.rs

@@ -37,10 +37,7 @@ fn get_metadata(playable: Option<Playable>) -> Metadata {
         Variant(Box::new(
             playable
                 .map(|t| {
-                    format!(
-                        "spotify:track:{}",
-                        t.id().unwrap_or_else(|| "0".to_string())
-                    )
+                    t.uri()
                 })
                 .unwrap_or_default(),
         )),
@@ -118,7 +115,13 @@ fn get_metadata(playable: Option<Playable>) -> Metadata {
     );
     hm.insert(
         "xesam:url".to_string(),
-        Variant(Box::new(playable.map(|t| t.uri()).unwrap_or_default())),
+        Variant(Box::new(
+            playable
+                .map(|t| {
+                    t.share_url().unwrap_or_default()
+                })
+                .unwrap_or_default(),
+        )),
     );
 
     hm