Fixed: Clean Artist Index Sort Menu, Fix Next/Last Album Sorting

Fixes #256

frontend/src/Artist/Index/Menus/ArtistIndexSortMenu.js

@@ -65,21 +65,21 @@ function ArtistIndexSortMenu(props) {
         </SortMenuItem>
 
         <SortMenuItem
-          name="nextAiring"
+          name="nextAlbum"
           sortKey={sortKey}
           sortDirection={sortDirection}
           onPress={onSortSelect}
         >
-          Next Airing
+          Next Album
         </SortMenuItem>
 
         <SortMenuItem
-          name="previousAiring"
+          name="lastAlbum"
           sortKey={sortKey}
           sortDirection={sortDirection}
           onPress={onSortSelect}
         >
-          Previous Airing
+          Last Album
         </SortMenuItem>
 
         <SortMenuItem
@@ -118,15 +118,6 @@ function ArtistIndexSortMenu(props) {
           Track Count
         </SortMenuItem>
 
-        <SortMenuItem
-          name="latestAlbum"
-          sortKey={sortKey}
-          sortDirection={sortDirection}
-          onPress={onSortSelect}
-        >
-          Latest Album
-        </SortMenuItem>
-
         <SortMenuItem
           name="path"
           sortKey={sortKey}

frontend/src/Store/Actions/artistIndexActions.js

@@ -163,6 +163,18 @@ export const defaultState = {
       return progress + trackCount / 1000000;
     },
 
+    nextAlbum: function(item) {
+      if (item.nextAlbum) {
+        return item.nextAlbum.title;
+      }
+    },
+
+    lastAlbum: function(item) {
+      if (item.lastAlbum) {
+        return item.lastAlbum.title;
+      }
+    },
+
     albumCount: function(item) {
       return item.statistics.albumCount;
     },