Update the notification icons for Lollipop

Repurposes one of the existing drawables and
includes a new drawable for multiple emails
inspired by the one used in the Gmail app

Change-Id: Ieb8589f38113e55d0170dcd204cd4f25ec2165ea
Change the Email widget to orange

Also update the update the widget preview
with the new look

Change-Id: I5a6571c1b1fec59ca42627ea404cb46c92eb7365
Fix the color of the Compose FAB

Also render it with mostly vector drawables

Change-Id: Ib19c0b4093a7c581481f7cab3c8b92fcf84f5b13