Add internal provisioner support matrix (#4009)

* Add internal provisioner support matrix

* Change links and add example of NFS plugin

* Remove usages related to hostpath

docs/concepts/storage/persistent-volumes.md

@@ -411,6 +411,27 @@ parameters:
 Storage classes have a provisioner that determines what volume plugin is used
 for provisioning PVs. This field must be specified.
 
+| Volume Plugin        | Internal Provisioner| Config Example                       |
+| :---                 |     :---:           |    :---:                             |
+| AWSElasticBlockStore | ✓            | [AWS](#aws)                          |
+| AzureFile            | ✓            | -                                    |
+| AzureDisk            | ✓            | [Azure Disk](#azure-disk)            |
+| CephFS               | -                   | -                                    |
+| Cinder               | ✓            | [OpenStack Cinder](#openstack-cinder)|
+| FC                   | -                   | -                                    |
+| FlexVolume           | -                   | -                                    |
+| Flocker              | ✓            | -                                    |
+| GCEPersistentDisk    | ✓            | [GCE](#gce)                          |
+| Glusterfs            | ✓            | [Glusterfs](#glusterfs)              |
+| iSCSI                | -                   | -                                    |
+| PhotonPersistentDisk | ✓            | -                                    |
+| Quobyte              | ✓            | [Quobyte](#quobyte)                  |
+| NFS                  | -                   | -                                    |
+| RBD                  | ✓            | [Ceph RBD](#ceph-rbd)                |
+| VsphereVolume        | ✓            | [vSphere](#vsphere)                  |
+| PortworxVolume       | ✓            | [Portworx Volume](#portworx-volume)  |
+| ScaleIO              | ✓            | [ScaleIO](#scaleio)                  |
+
 You are not restricted to specifying the "internal" provisioners
 listed here (whose names are prefixed with "kubernetes.io" and shipped
 alongside Kubernetes). You can also run and specify external provisioners,
@@ -421,6 +442,11 @@ run, what volume plugin it uses (including Flex), etc. The repository [kubernete
 houses a library for writing external provisioners that implements the bulk of
 the specification plus various community-maintained external provisioners.
 
+For example, NFS doesn't provide an internal provisioner, but an external provisioner
+can be used. Some external provisioners are listed under the repository [kubernetes-incubator/external-storage](https://github.com/kubernetes-incubator/external-storage).
+There are also cases when 3rd party storage vendors provide their own external
+provisioner.
+
 ### Parameters
 Storage classes have parameters that describe volumes belonging to the storage
 class. Different parameters may be accepted depending on the `provisioner`. For