Add a "Select all" button to inbox/things/rules

[mueller-ma]

The problem

It can be cumbersome to approve multiple new Things in the inbox, because you have to click on "Select" and check every single new Thing.

Your suggestion

Add a new button "Select all" to lists that already have a "Select" options, e.g. Things, Thing Inbox, Rules, Items, etc.:

Your environment

runtimeInfo:
  version: 4.1.2
  buildString: Release Build

Additional information

This is similar to #901, but more general.

[Richard Koshak]

Would one be able to "select all" and then remove from the selection? That's an important use case that isn't always implemented so I want to make sure it's not forgotten.