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/rowkeys_qwerty2.xml b/java/res/xml/rowkeys_qwerty2.xml
index 2fa8214..a29f331 100644
--- a/java/res/xml/rowkeys_qwerty2.xml
+++ b/java/res/xml/rowkeys_qwerty2.xml
@@ -23,28 +23,28 @@
 >
     <Key
         latin:keyLabel="a"
-        latin:moreKeys="@string/more_keys_for_a" />
+        latin:moreKeys="!label/more_keys_for_a" />
     <Key
         latin:keyLabel="s"
-        latin:moreKeys="@string/more_keys_for_s" />
+        latin:moreKeys="!label/more_keys_for_s" />
     <Key
         latin:keyLabel="d"
-        latin:moreKeys="@string/more_keys_for_d" />
+        latin:moreKeys="!label/more_keys_for_d" />
     <Key
         latin:keyLabel="f" />
     <Key
         latin:keyLabel="g"
-        latin:moreKeys="@string/more_keys_for_g" />
+        latin:moreKeys="!label/more_keys_for_g" />
     <Key
         latin:keyLabel="h"
-        latin:moreKeys="@string/more_keys_for_h" />
+        latin:moreKeys="!label/more_keys_for_h" />
     <Key
         latin:keyLabel="j"
-        latin:moreKeys="@string/more_keys_for_j" />
+        latin:moreKeys="!label/more_keys_for_j" />
     <Key
         latin:keyLabel="k"
-        latin:moreKeys="@string/more_keys_for_k" />
+        latin:moreKeys="!label/more_keys_for_k" />
     <Key
         latin:keyLabel="l"
-        latin:moreKeys="@string/more_keys_for_l" />
+        latin:moreKeys="!label/more_keys_for_l" />
 </merge>