A predefined action id replaces the label in the enter key with an icon.

Balanced all icons to use the same aspect ratio. Removed all custom
margins used for icon positioning and sizing.

Task-number: QTRD-2900
Change-Id: I159bcb4d53e8ceb8f51f4a8be24504e20262f37a
Reviewed-by: Mitch Curtis <mitch.curtis@digia.com>
Reviewed-by: Rainer Keller <rainer.keller@digia.com>