Overprovision should be default true. Terraform and the service back … (

#1322)

* Overprovision should be default true. Terraform and the service back end is considering this as default false when nothing is specified.

* Updating the documentation to reflect the change

* Changing the sentence based on code review

* Quoting the `true` values

azurerm/resource_arm_virtual_machine_scale_set.go

@@ -106,6 +106,7 @@ func resourceArmVirtualMachineScaleSet() *schema.Resource {
 			"overprovision": {
 				Type:     schema.TypeBool,
 				Optional: true,
+				Default:  true,
 			},
 
 			"single_placement_group": {

website/docs/r/virtual_machine_scale_set.html.markdown

@@ -245,8 +245,8 @@ The following arguments are supported:
 * `location` - (Required) Specifies the supported Azure location where the resource exists. Changing this forces a new resource to be created.
 * `sku` - (Required) A sku block as documented below.
 * `upgrade_policy_mode` - (Required) Specifies the mode of an upgrade to virtual machines in the scale set. Possible values, `Manual` or `Automatic`.
-* `overprovision` - (Optional) Specifies whether the virtual machine scale set should be overprovisioned.
-* `single_placement_group` - (Optional) Specifies whether the scale set is limited to a single placement group with a maximum size of 100 virtual machines. If set to false, managed disks must be used. Default is true. Changing this forces a
+* `overprovision` - (Optional) Specifies whether the virtual machine scale set should be overprovisioned. Defaults to `true`.
+* `single_placement_group` - (Optional) Specifies whether the scale set is limited to a single placement group with a maximum size of 100 virtual machines. If set to false, managed disks must be used. Defaults to `true`. Changing this forces a
     new resource to be created. See [documentation](http://docs.microsoft.com/en-us/azure/virtual-machine-scale-sets/virtual-machine-scale-sets-placement-groups) for more information.
 * `license_type` - (Optional, when a Windows machine) Specifies the Windows OS license type. If supplied, the only allowed values are `Windows_Client` and `Windows_Server`.
 * `os_profile` - (Required) A Virtual Machine OS Profile block as documented below.