FEATURE: Selection and editing of multiple assets

[connykaelinvisol]

What I did
Multiple Assets are selectable by checkbox or with shift/command in thumbnail and list view. The possible actions for the selected Assets are:

• Delete
• Add/remove to clipboard
• Set copyrightNote (the same for all selected Assets, overwrites already existing copyrightNotes)
• Move to Asset collection
• Add/remove Tags

With this change some design adjustments were made too for thumbnail and list view. Also the delete button inside the clipboard was removed and a new button to close the clipboard was added. The function of the clipboard (as short path to files) was not touched.

How to verify it
There is a new set of e2e tests bundled in Multi-Selection.

Resolves: #30 #81 #8

[Sebobo]

Thx, already looks and works great!

A few things I noticed so far during review:

1. Selection view allows multi select, but it doesn't have any use and the selection icon is broken. I would only allow the feature in the media module for now.

2. The context menu doesn't look so good yet, especially in the detail view. Also the delete button doesn't make sense there, if we are currently inspecting an asset that is in use. We should remove the delete button in this view and improve the menu styling.

3. You added most code to the core package, which I want to cleanup. Can we move at least a part of the batch / multi functionality to a separate package?

I merged the changes from 2.x.dev and fixed a few minor things related to my api changes (all operations now need an asset source id).

[connykaelinvisol]

@Sebobo point 1 and 2 are fixed/improved. I also extracted some of the newly created hooks from the core package which are only consumed by components from the media-module package. other code like states are consumed by code in different packages so there is no distinct allocation possible.

I left the badge component in the core too even if we only use it in the media-module component for now. This is a quite basic component which can be reused anywhere if needed.