Ubuntu: hide e-mail headers when scrolling one message

By turning on the flickable property of the Page, scrolling the actual message contents properly hides the header.

REVIEW: 117502
Ubuntu: Imap Settings re-work

The Imap settings page is now part of a tabbed component so we can group
all
settings pages together similar to desktop version.

Settings page now validates user input on required username and server
name fields. Presenting red placeholder text if failed validation.

Page now has a toolbar to save settings or delete current settings
if the user wishes to change them. With a dialog to confirm user
wishes to delete current settings.

So now if the user already has a configured account the first page they
see
is the Mailbox view and get prompted for password. The user can still
access
settings from the toolbar

Added save.svg and settings.svg both are from the ubuntu-mobile-icons
package
available from http://packages.ubuntu.com/trusty/all/ubuntu-mobile-
and is available under the CC-BY-SA 3.0. Copyright by 2004-2012,
Canonical Ltd.

REVIEW:117504