Auto add new words to the user dictionary.

First pass at automatically adding new words that the user types and deliberately
accepts.
After typing the word 4 times, the word gets promoted to being valid.
After typing the word 7 times, the word gets added into the UserDictionary and can
be removed from the UserDictionary Settings UI.

Also add a second row of symbols to the period popup.
diff --git a/res/xml/popup_punctuation.xml b/res/xml/popup_punctuation.xml
index 9d4575d..7f9f611 100644
--- a/res/xml/popup_punctuation.xml
+++ b/res/xml/popup_punctuation.xml
@@ -25,7 +25,16 @@
     android:keyHeight="@dimen/key_height"
     >
 
-    <Row android:rowEdgeFlags="top|bottom">
+    <Row android:rowEdgeFlags="top">
+        <Key android:keyLabel=";" android:keyEdgeFlags="left" />
+        <Key android:keyLabel="\\" />
+        <Key android:keyLabel="&amp;" />
+        <Key android:keyLabel="(" />
+        <Key android:keyLabel=")" />
+        <Key android:keyLabel="-" />
+        <Key android:keyLabel="+" android:keyEdgeFlags="right" />
+    </Row>
+    <Row android:rowEdgeFlags="bottom">
         <Key android:codes="58" android:keyLabel=":" android:keyEdgeFlags="left" />
         <Key android:codes="47" android:keyLabel="/" />
         <Key android:codes="64" android:keyLabel="\@" />