Updates for K8 client package

[jrnt30]

• Adds in error messages for pod interface failures
• Updates K8 client-go to 1.10 version
• Adjusts travis CI docker push to not tag with latest for RC builds

[coveralls]

Coverage increased (+0.2%) to 19.946% when pulling 1f474ad on 1.10-api into d1ede0d on master.

[geekofalltrades]

As a bonus, this MR pulls in a version of client-go that has switched from glog to klog, so that the process doesn't just randomly die sometimes if it can't write a file in /tmp. We hit this a lot in our environment, where we're running kube2iam from a scratch container; our kube2iam pods have all died and restarted hundreds of times.

[wamarcantel]

@jtblin Can we get this merged any time soon?

[angulito]

any news about merging this PR? it will fix the read-only issue with /tmp - thank you!