Description of problem:
We have some interactive operations in atomic command, it will be convenient for users if we can support for automatically answer yes for all questions like '--assumeyes' option in dnf.


Version-Release number of selected component (if applicable):

[cloud-user@atomic-host-001 atomic]$ cat /etc/redhat-release 
Red Hat Enterprise Linux Atomic Host release 7.2

[cloud-user@atomic-host-001 atomic]$ atomic host status
State: idle
Deployments:
● rhel-atomic-host-ostree:rhel-atomic-host/7/x86_64/standard
       Version: 7.2.7 (2016-08-25 18:18:13)
        Commit: 2c31fbe0af5f907dc541bf23cc8a1ba18bcf9f1d0a74fdcdb17d25043f296d1c
        OSName: rhel-atomic-host

[cloud-user@atomic-host-001 atomic]$ rpm -q atomic
atomic-1.10.5-7.el7.x86_64

How reproducible:
always.

Steps to Reproduce:
1. docker pull some images to local
2. atomic storage export --dir /tmp/export
3. systemctl stop docker
4. atomic storage reset
5. systemctl start docker
6. atomic storage import --dir /tmp/export

Actual results:

[cloud-user@atomic-host-001 atomic]$ sudo ./atomic storage import --dir /tmp/export
Importing image: 11a5107645d4
Importing image: 2b8fd9751c4c
Importing container: 911a6948348b
Importing volumes
atomic import completed successfully
Would you like to cleanup (rm -rf /tmp/export) the temporary directory [y/N]

Expected results:
support for automatically answer yes for all questions

Additional info:

PR: https://github.com/projectatomic/atomic/pull/573