Send refreshRequested broadcast to installed API packages.

When a new package is installed that supports the CM Home API, request a
refresh so that the new application can start up and provide cards.

Change-Id: I1653be504e34ee24dc7c80dd93c612051119e5ec
Post all CM Home Api Card updates to a single background thread.

Creating new AsyncTask instances for various updates from API Content
Observers created a variety of race conditions. Processing of updates
must occur in order. Use a single background thread and post all card
operations as a runnable to a Handler running on this thread.

Change-Id: I6f79e9e2c846cc5a59a3e5e28901b2e7795fa639
Properly handle the first card inserted for an extension.

Add two missing lines to properly store images and notify listeners for
the first card inserted by an extension.

Change-Id: I891c9005dc8558e0631271d876950ef5fea42e1a
Track whether updates have been handled.

Store whether card updates have been handled by the listener. If they
have not, any updates should notify the listener and not be held back as
pending.

Change-Id: I333211065b300ca0e13de03bedadf31796de390e