Modules: create private flavors by default

Add "flavor_is_public" variable to the "flavor" module with "false"
value by default.

modules/flavor/main.tf

@@ -1,6 +1,7 @@
 resource "openstack_compute_flavor_v2" "flavor_1" {
-  name  = "${var.flavor_name}"
-  ram   = "${var.flavor_ram_mb}"
-  vcpus = "${var.flavor_vcpus}"
-  disk  = "${var.flavor_local_disk_gb}"
+  name      = "${var.flavor_name}"
+  ram       = "${var.flavor_ram_mb}"
+  vcpus     = "${var.flavor_vcpus}"
+  disk      = "${var.flavor_local_disk_gb}"
+  is_public = "${var.flavor_is_public}"
 }

modules/flavor/vars.tf

@@ -17,3 +17,8 @@ variable "flavor_local_disk_gb" {
   description = "Amount of GB for local storage of the OpenStack Compute Flavor"
   default     = 0
 }
+
+variable "flavor_is_public" {
+  description = "Flavor visibility"
+  default     = false
+}