Add unifi_static_route

Fixes #42

examples/resources/unifi_static_route/resource.tf

@@ -0,0 +1,22 @@
+resource "unifi_static_route" "nexthop" {
+  type     = "nexthop-route"
+  network  = "172.17.0.0/16"
+  name     = "basic nexthop"
+  distance = 1
+  next_hop = "172.16.0.1"
+}
+
+resource "unifi_static_route" "blackhole" {
+  type     = "blackhole"
+  network  = var.blackhole_cidr
+  name     = "blackhole traffice to cidr"
+  distance = 1
+}
+
+resource "unifi_static_route" "interface" {
+  type      = "interface-route"
+  network   = var.wan2_cidr
+  name      = "send traffic over wan2"
+  distance  = 1
+  interface = "WAN2"
+}