Remove account-plugin-evernote from phone image

We want to ship an evernote accounts plugin in the reminders-app click package. As such we no longer need the account-plugin-evernote in the image.

Note: the main reason for the move is that we want to ship the Evernote API key in the Reminders app click package instead of a .deb package. This way we're not tied to system updates if the key needs to be updated or revoked. In addition to that, we can get Jenkins to manage the API keys and keep them private instead of making them public.

This needs to be coordinated with an upload of the new Reminders app that includes the account in the click package: https://bugs.launchpad.net/reminders-app/+bug/1367235