Update labels.yaml

Reminder that at some point we need to stop allowing humans to add
labels via github's UI, and instead drive changes through this file.

labels.yaml

@@ -4,6 +4,8 @@ repo: kubernetes/kubernetes
 labels:
 - name: approved
   color: 0ffa16
+- name: approved-for-milestone
+  color: fef2c0
 - name: area/admin
   color: 0052cc
 - name: area/admission-control
@@ -48,12 +50,16 @@ labels:
   color: 0052cc
 - name: area/HA
   color: 0052cc
+- name: area/hw-accelerators
+  color: 0052cc
 - name: area/images-registry
   color: 0052cc
 - name: area/ingress
   color: 0052cc
 - name: area/introspection
   color: 0052cc
+- name: area/ipv6
+  color: 0052cc
 - name: area/isolation
   color: 0052cc
 - name: area/kube-proxy
@@ -92,6 +98,8 @@ labels:
   color: d4c5f9
 - name: area/platform/gke
   color: d4c5f9
+- name: area/platform/mesos
+  color: d4c5f9
 - name: area/platform/vagrant
   color: d4c5f9
 - name: area/platform/vsphere
@@ -180,6 +188,8 @@ labels:
   color: f7c6c7
 - name: kind/friction
   color: c7def8
+- name: kind/mesos-flake
+  color: f7c6c7
 - name: kind/new-api
   color: c7def8
 - name: kind/old-docs
@@ -200,6 +210,8 @@ labels:
   color: b60205
 - name: needs-rebase
   color: BDBDBD
+- name: needs-sig
+  color: ededed
 - name: non-release-blocker
   color: 0e8a16
 - name: ok-to-merge
@@ -252,12 +264,16 @@ labels:
   color: d2b48c
 - name: sig/apps
   color: d2b48c
+- name: sig/architecture
+  color: d2b48c
 - name: sig/auth
   color: d2b48c
 - name: sig/autoscaling
   color: d2b48c
 - name: sig/aws
   color: d2b48c
+- name: sig/azure
+  color: d2b48c
 - name: sig/big-data
   color: d2b48c
 - name: sig/cli
@@ -282,6 +298,8 @@ labels:
   color: d2b48c
 - name: sig/openstack
   color: d2b48c
+- name: sig/release
+  color: d2b48c
 - name: sig/rktnetes
   color: d2b48c
 - name: sig/scalability
@@ -294,6 +312,8 @@ labels:
   color: d2b48c
 - name: sig/testing
   color: d2b48c
+- name: sig/ui
+  color: d2b48c
 - name: sig/windows
   color: d2b48c
 - name: size/L
@@ -310,6 +330,10 @@ labels:
   color: ee0000
 - name: stale
   color: "795548"
+- name: status/in-progress
+  color: fef2c0
+- name: status/in-review
+  color: fef2c0
 - name: team/api (deprecated - do not use)
   color: ededed
 - name: team/cluster (deprecated - do not use)
@@ -320,6 +344,8 @@ labels:
   color: d2b48c
 - name: team/huawei
   color: d2b48c
+- name: team/mesosphere
+  color: d2b48c
 - name: team/redhat
   color: d2b48c
 - name: team/test-infra