Make editing image related blocks more consistent

[dennisheiden]

Currently we have 3 image related blocks with 3 different ways to edit:

• Image -> double click the image -> click button
• Gallery -> click on image -> click on button
• Media-Text -> click on image -> click on he pencil icon in the toolbar

I think this is not very convenient and would be more streamlined if the buttons (+ other options) get visible with double click on the image and with one click on the pencil icon in the toolbar you get the media popup.

Therefore you have to remember only one way to edit, not 3.