Separated database table logic and added SocialProvider.

Created a second ContentProvider to handle social stream data, called
"Activities" here.  Designed schema after the data provided by various
online stream sources, including the "Atom Activity Extensions" RFC
Internet-Draft available at http://activitystrea.ms/.

Because social data references Contacts data directly by _ID, we keep
the data behind both ContentProviders in a single database to improve
join query performance.

To make sure that both ContentProviders use the same underlying
database through a single SQLiteDatabase instance, we only allow access
to OpenHelper as a singleton.
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 4b0230e..52d5d44 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -6,14 +6,21 @@
     <uses-permission android:name="android.permission.WRITE_CONTACTS" />
 
     <application
-        android:label="ContactsProvider2"
-    >
+        android:label="ContactsProvider2">
+
         <provider android:name="ContactsProvider2"
             android:authorities="com.android.contacts"
             android:syncable="false"
             android:multiprocess="false"
             android:readPermission="android.permission.READ_CONTACTS"
-            android:writePermission="android.permission.WRITE_CONTACTS"
-        />
+            android:writePermission="android.permission.WRITE_CONTACTS" />
+
+        <!-- TODO: create permissions for social data -->
+        <provider android:name="SocialProvider"
+            android:authorities="com.android.social"
+            android:syncable="false"
+            android:multiprocess="false"
+            android:readPermission="android.permission.READ_CONTACTS"
+            android:writePermission="android.permission.WRITE_CONTACTS" />
     </application>
 </manifest>