Minor phrasing fix

Author: yuvipanda

commons/res/values/strings.xml

@@ -50,7 +50,7 @@
     <string name="login_failed_generic">Login failed</string>
 
     <string name="share_upload_button">Upload</string>
-    <string name="multiple_share_base_title">Base Title</string>
+    <string name="multiple_share_base_title">Name this set</string>
 
     <plurals name="contributions_subtitle">
         <item quantity="zero">No uploads yet</item>