Generate KeyboardLabelsSet from donottranslate-more-keys.xml

This change introduces makelabel tool that reads all languages'
donottranslate-more-keys and generate KeyboardLabelsSet.java source
file. The makelabel command must be invoked prior to compile LatinIME.

Change-Id: I7515c7919c535e30f9c80a37bdc831d0f682cd43
diff --git a/java/res/xml-sw768dp/rows_symbols4.xml b/java/res/xml-sw768dp/rows_symbols4.xml
index 19b36d6..dd1647b 100644
--- a/java/res/xml-sw768dp/rows_symbols4.xml
+++ b/java/res/xml-sw768dp/rows_symbols4.xml
@@ -37,7 +37,7 @@
             latin:keyWidth="37.500%p" />
         <Key
             latin:keyLabel="&quot;"
-            latin:moreKeys="@string/more_keys_for_tablet_double_quote" />
+            latin:moreKeys="!label/more_keys_for_tablet_double_quote" />
         <Key
             latin:keyLabel="_" />
         <switch>