kairos-agent enhancements for cloud-image management

[nano2007]

The elemental cli command has been removed and we have to use kairos-agent to perform the reset for booting a cloud-image. But the kairos-agent cli needs a few enhancements to work for this usecase:

1. skip the 60 second wait before reset and another 60 second delay before reboot.
2. add flag to skip the reboot so that we can do any other housekeeping (touch /usr/local/.deployed in this case)