New design for Conversation Activity.

1) Move to Fragments for the list view.
2) Switch to CursorLoader from my jankey self-managed cursor.
3) Add session security logic to the ActionBar.
4) Fix colors to be less ugly.

res/menu/conversation_insecure.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:title="Security"
+          android:id="@+id/menu_security"
+          android:icon="@drawable/ic_menu_lock_holo_dark"
+          android:showAsAction="ifRoom">
+          <menu>
+              <item android:title="Start Secure Session"
+                    android:id="@+id/menu_start_secure_session" />
+
+          </menu>
+    </item>
+</menu>