Bug 83608, change wording/accesskey for prefs->advanced->cache. r=blake, sr=darin

suite/locales/en-US/chrome/common/pref/pref-cache.dtd

@@ -24,5 +24,5 @@
 <!ENTITY  everyTimeRadio.accesskey      "e">
 <!ENTITY  neverRadio.label              "Never">
 <!ENTITY  neverRadio.accesskey          "n">
-<!ENTITY  autoRadio.label               "Automatically">
-<!ENTITY  autoRadio.accesskey           "a">
+<!ENTITY  autoRadio.label               "When the page is out of date">
+<!ENTITY  autoRadio.accesskey           "w">