bf4f84167f
Automatic merge from submit-queue Add init containers to pods This implements #1589 as per proposal #23666 Incorporates feedback on #1589, creates parallel structure for InitContainers and Containers, adds validation for InitContainers that requires name uniqueness, and comments on a number of implications of init containers. This is a complete alpha implementation. <!-- Reviewable:start --> --- This change is [<img src="http://reviewable.k8s.io/review_button.svg" height="35" align="absmiddle" alt="Reviewable"/>](http://reviewable.k8s.io/reviews/kubernetes/kubernetes/23567) <!-- Reviewable:end -->
