Description of problem:
The content in configmap is hard to read and maintain and is error-prone.

Version-Release number of the following components:
openshift-ansible-3.10.0-0.22.0.git.0.b6ec617.el7

How reproducible:
Always

Steps to Reproduce:
1. try to modify configmap
# oc edit cm node-config-master -n openshift-node

Actual results:

apiVersion: v1
data:
  node-config.yaml: "kind: NodeConfig\napiVersion: v1\nauthConfig:\n  authenticationCacheSize:
    1000\n  authenticationCacheTTL: 5m\n  authorizationCacheSize: 1000\n  authorizationCacheTTL:
    5m\ndnsBindAddress: \"127.0.0.1:53\"\ndnsDomain: cluster.local\ndnsIP: 0.0.0.0\ndnsNameservers:
    null\ndnsRecursiveResolvConf: /etc/origin/node/resolv.conf\ndockerConfig:\n  dockerShimRootDirectory:
    /var/lib/dockershim\n  dockerShimSocket: /var/run/dockershim.sock\n  execHandlerName:
    native\nenableUnidling: true\nimageConfig:\n  format: \"registry.reg-aws.openshift.com:443/openshift3/ose-${component}:v3.10\"\n
    \ latest: false\niptablesSyncPeriod: 30s\nkubeletArguments:\n  pod-manifest-path:\n
    \ - /etc/origin/node/pods\n  bootstrap-kubeconfig:\n  - /etc/origin/node/bootstrap.kubeconfig\n
    \ feature-gates:\n  - RotateKubeletClientCertificate=true,RotateKubeletServerCertificate=true\n
    \ rotate-certificates:\n  - \"true\"\n  cert-dir:\n  - /etc/origin/node/certificates\n
    \ cloud-config:\n  - /etc/origin/cloudprovider/aws.conf\n  cloud-provider:\n  -
    aws\n  node-labels: \n  - \"node-role.kubernetes.io/master=true\"\n  enable-controller-attach-detach:\n
    \ - 'true'\nmasterClientConnectionOverrides:\n  acceptContentTypes: application/vnd.kubernetes.protobuf,application/json\n
    \ burst: 40\n  contentType: application/vnd.kubernetes.protobuf\n  qps: 20\nmasterKubeConfig:
    node.kubeconfig\nnetworkConfig:\n  mtu: 8951\n  networkPluginName: redhat/openshift-ovs-networkpolicy\nservingInfo:\n
    \ bindAddress: 0.0.0.0:10250\n  bindNetwork: tcp4\n  clientCA: client-ca.crt\nvolumeConfig:\n
    \ localQuota:\n    perFSGroup: null\nvolumeDirectory: /var/lib/origin/openshift.local.volumes\n"
kind: ConfigMap


Expected results:
style easy to read and understand by human

kind: NodeConfig
apiVersion: v1
authConfig:
  authenticationCacheSize: 1000
  authenticationCacheTTL: 5m
  authorizationCacheSize: 1000
  authorizationCacheTTL: 5m
dnsBindAddress: "127.0.0.1:53"
dnsDomain: cluster.local
dnsIP: 0.0.0.0
dnsNameservers: null
dnsRecursiveResolvConf: /etc/origin/node/resolv.conf
dockerConfig:
  dockerShimRootDirectory: /var/lib/dockershim
  dockerShimSocket: /var/run/dockershim.sock
  execHandlerName: native
enableUnidling: true
imageConfig:
  format: "registry.reg-aws.openshift.com:443/openshift3/ose-${component}:v3.10"
  latest: false
iptablesSyncPeriod: 30s