Add the Copy button to the full view in the Administration Interface

[pkamps]

Upstream pull request: ezsystems#1413

Original description:
https://jira.ez.no/browse/EZP-29983

In the eZ back-end you have Edit / Move / Remove on the page you're viewing

But to copy, you have to initiate it from the "Sub items" window. No more! We will add the Copy button to the full view as well!

[thiagocamposviana]

@pkamps I see the button in the admin interface and it works, only issue is that there is a style:

.controlbar form .button-left .block input.button, .controlbar form .button-left .block input.button-disabled, .controlbar form .button-left .block a.button, .controlbar form .button-left .block a.button-disabled {
    margin-top: -3px;
}

Making the buttons not aligned.