Document minimal permissions (#175)

README.md

@@ -133,3 +133,28 @@ Only use the `cluster` option. Optionally specify a `resource_pool`:
 "cluster": "cluster2",
 "resource_pool": "pool1",
 ```
+
+## Required vSphere Permissions
+Read only (without propagation) is required for:
+```
+vcenter -> datacenter -> cluster
+vcenter -> datacenter -> distributed switch
+```
+Required for any: resource pool, folder, distributed port group, datastore or storage cluster (with propagation) used in the builder:
+```
+Datastore ->Allocate space
+Datastore ->Browse datastore
+Datastore ->Low level file operations
+Datastore ->Remove file
+Datastore ->Update virtual machine files
+Datastore ->Update virtual machine metadata
+Network -> Assign network
+Resource -> Assign virtual machine to resource pool
+Virtual machine -> Change Configuration
+Virtual machine -> Edit Inventory
+Virtual machine -> Guest operations
+Virtual machine -> Interaction
+Virtual machine -> Provisioning
+Virtual machine -> Service configuration
+Virtual machine -> Snapshot management
+```