Updated and added some translation strings

Output/PartyModes/Challenge/Languages/English.xml

@@ -11,6 +11,7 @@
   <string name="TR_BUTTON_YES">Yes</string>
   <string name="TR_BUTTON_NO">No</string>
   <string name="TR_BUTTON_NEXT_ROUND">Next Round</string>
+  <string name="TR_SONGS">Songs</string>
   <string name="TR_SCREENCONFIG_TITLE">Challenge Mode: Configuration</string>
   <string name="TR_SCREENCONFIG_NUMPLAYERS">Number of players</string>
   <string name="TR_SCREENCONFIG_NUMMICS">Number of mics</string>

Output/PartyModes/Challenge/Themes/Default/Screens/PartyScreenChallengeSongs.xml

@@ -53,7 +53,7 @@
       <ResizeAlign>Center</ResizeAlign>
       <Style>Bold</Style>
       <Font>Outline</Font>
-      <Text>TR_SCREENCONFIG_SONGSOURCE</Text>
+      <Text>TR_SONGSOURCE</Text>
     </Text>
     <Text Name="TextSongMode">
       <X>75</X>
@@ -67,7 +67,7 @@
       <ResizeAlign>Center</ResizeAlign>
       <Style>Bold</Style>
       <Font>Outline</Font>
-      <Text>TR_SCREENCONFIG_GAMEMODE</Text>
+      <Text>TR_GAMEMODE</Text>
     </Text>
   </Texts>
   <Buttons>