Add strings for hierarchical folders

We need these translated

Bug: 9604590
Change-Id: I2f0bc7e23293556be6ded37eb54d30b65d31ac72
diff --git a/res/values/strings.xml b/res/values/strings.xml
index d4106d6..5453934 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -935,4 +935,8 @@
          LIMIT=30] -->
     <string name="turn_auto_sync_on_dialog_confirm_btn">Turn on</string>
 
+    <!-- Button in conversation list to show more folders [CHAR LIMIT=50] -->
+    <string name="show_n_more_folders">Show <xliff:g id="number">%1$s</xliff:g> more folders</string>
+    <!-- Button in conversation list to hide folders [CHAR LIMIT=50] -->
+    <string name="hide_folders">Hide folders</string>
 </resources>