**Summary**
When adding container images we will only get an output AFTER everything has been downloaded.
This makes the CLI feel stalled while loading huge images.
```
vyos@vyos:~$ add container image docker.io/dchidell/docker-tacacs:latest
... wait ...
Trying to pull docker.io/dchidell/docker-tacacs:latest...
Getting image source signatures
Copying blob sha256:a437dd5e1c95d8be83c99136acafe5715f759d92283a511571894f72280347d7
Copying blob sha256:bb475c5a1679a449fb8a5f1ec7718a271361d8df0dec16eded0b8ec79c62c190
Copying blob sha256:9d96cc944b9b157345410e6e6ed3188e400ba3fd9e0e90cecdb20c16abd8f96c
Copying blob sha256:31189a86500e131c281b9a272e5180e6985b6fbad91fa7fad0cd22ba5536822f
Copying blob sha256:596ba82af5aaa3e2fd9d6f955b8b94f0744a2b60710e3c243ba3e4a467f051d1
Copying blob sha256:55cc45e63c72bfe0f3ac8b2a73518f8d49fd3cbc59a82c64bc5ee1fdd587b209
Copying blob sha256:96f1df4f8b2a3fdd61f3dac7297d5a54c604cfd804387cd6dee2fc87a1571b3f
Copying config sha256:84f7fe4db64b27fdc663001bf5d0fb486939520242b704e79c07135f0fb975f7
Writing manifest to image destination
84f7fe4db64b27fdc663001bf5d0fb486939520242b704e79c07135f0fb975f7
```
**Use case**
[Example: "802.1q VLAN interfaces are widely used for traffic separation in switched networks and for "router on a stick" scenarios. Most router vendors support them.]
**Additional information**
[Add anything you think is important for maintainers to understand your feature idea.]