Favorites on the login screen

Adds some guts for the favorites bar, I'll get to that eventually

indra/newview/app_settings/settings_per_account.xml

@@ -770,6 +770,17 @@
       <key>Value</key>
       <string>-%Y-%m</string>
     </map>
+    <key>ShowFavoritesOnLogin</key>
+        <map>
+        <key>Comment</key>
+             <string>Determines whether favorites of last logged in user will be saved on exit from viewer and shown on login screen</string>
+        <key>Persist</key>
+             <integer>1</integer>
+        <key>Type</key>
+             <string>Boolean</string>
+        <key>Value</key>
+             <integer>1</integer>
+        </map>
 
     <key>KeywordsChangeColor</key>
     <map>