Feature: #64286 - Added absolute url option to uri.image and image viewHelper

Description

The ImageViewhelper and Uri/ImageViewHelper got a new option absolute. With this option you are able to force the ViewHelpers to output an absolute url.

Examples:

<code title="ImageViewHelper">
    <f:image image="{file}" width="400" height="375" absolute="1" />
</code>
<output>
    <img alt="alt set in image record" src="http://www.mydomain.com/fileadmin/_processed_/323223424.png" width="400" height="375" />
</output>

<code title="Uri/ImageViewHelper">
    <f:uri.image image="{file}" width="400" height="375" absolute="1" />
</code>
<output>
    http://www.mydomain.com/fileadmin/_processed_/323223424.png
</output>