More capabilities for default home configuration

More capabilities for default home configuration

Added support for adding appwidgets beyond clock and search to the
intital configuration. Also pulled in a previous change in Launcher that
allowed http shortcuts. New syntax looks like this in
default_workspace.xml:

     <appwidget
        launcher:packageName="com.android.settings"
        launcher:className="com.android.settings.widget.SettingsAppWidgetProvider"
        launcher:screen="0"
        launcher:x="0"
        launcher:y="2"
        launcher:spanX="4"
        launcher:spanY="1" />

    <shortcut
        launcher:packageName="com.android.settings"
        launcher:icon="@drawable/ic_launcher_appwidget"
        launcher:title="@string/group_folder"
        launcher:uri="http://www.nytimes.com"
        launcher:screen="2"
        launcher:x="2"
        launcher:y="2" />