tab: switch between artist and album search

src/sh/api.sh

@@ -52,7 +52,7 @@ api_mb_browse_releasegroup_releases() {
 }
 
 # Argument: Search string
-api_mb_search_artists() {
+api_mb_search_artist() {
   $CURL \
     --get \
     --data fmt=json \
@@ -61,6 +61,15 @@ api_mb_search_artists() {
     "https://musicbrainz.org/ws/2/artist"
 }
 
+api_mb_search_releasegroup() {
+  $CURL \
+    --get \
+    --data fmt=json \
+    --data-urlencode query="$1" \
+    -A "$APP_NAME/$APP_VERSION ($APP_WEBSITE)" \
+    "https://musicbrainz.org/ws/2/release-group"
+}
+
 api_discogs_artist() {
   $CURL \
     --get \