Support extended pod logging options

Increase the supported controls on pod logging. Add validaiton to pod
log options. Ensure the Kubelet is using a consistent, structured way to
process pod log arguments.

Add ?sinceSeconds=<durationInSeconds>, &sinceTime=<RFC3339>, ?timestamps=<bool>,
?tailLines=<number>, and ?limitBytes=<number>

hack/verify-flags/known-flags.txt

@@ -1,3 +1,4 @@
+
 accept-hosts
 accept-paths
 account-for-pod-resources
@@ -142,6 +143,7 @@ kube-master
 label-columns
 last-release-pr
 legacy-userspace-proxy
+limit-bytes
 load-balancer-ip
 log-flush-frequency
 long-running-request-regexp
@@ -251,6 +253,8 @@ service-node-port-range
 service-node-ports
 service-sync-period
 session-affinity
+since-seconds
+since-time
 show-all
 shutdown-fd
 shutdown-fifo
@@ -286,3 +290,4 @@ www-prefix
 retry_time
 file_content_in_loop
 cpu-cfs-quota
+