update deployment for k8s v1.16 (k8snetworkplumbingwg#183)

- New daemonset to support k8s v1.16
  - Moved daemonsets into K8s versions specific dir
  - Removed redundant/not-used sample deployments
  - Moved Dockerfile into image/
  - Removed additional daemonset yaml from docs/dpdk and docs/rdma

rename Dockerfile.rhel to Dockerfile.rhel7 and multi-stage build

build cni binary with static libraries (k8snetworkplumbingwg#119)

Pull the latest image for daemon set

With policy = Never, the image won't be pulled by kubelet, meaning the
deployment will fail to start pods due to missing image in registry.

allowing proxy-settings to be passed in for Docker

This changes will allow proxy settings to be passed in for docker
as well as Env variable in Dockerfile.

simply invoke 'make image HTTP_PROXY=http://whateverhost:port'.

Change-Id: I4264b2a96d86a6feedee1b21a9f1bac8e74c8fc5

requries K8s patch. DP has CNI endpoint