Gateway API support (#117)

This change adds support for the new proxy service to the operator
through Gateway API. This change attempts to standardize concepts around
the Gateway API to allow for compatibility with other projects.

Fixes #111
Fixes #44

Signed-off-by: Philip Laine <philip.laine@gmail.com>

examples/gateway-api/gateway.yaml

@@ -0,0 +1,30 @@
+apiVersion: gateway.networking.k8s.io/v1
+kind: GatewayClass
+metadata:
+  name: public
+spec:
+  controllerName: "gateway.netbird.io/controller"
+---
+apiVersion: gateway.networking.k8s.io/v1
+kind: Gateway
+metadata:
+  name: netbird
+  namespace: netbird
+spec:
+  gatewayClassName: public
+  listeners:
+  - protocol: HTTP
+    port: 80
+    name: dummy
+  infrastructure:
+    parametersRef:
+      group: netbird.io
+      kind: NBRoutingPeer
+      name: netbird
+---
+apiVersion: netbird.io/v1
+kind: NBRoutingPeer
+metadata:
+  name: netbird
+  namespace: netbird
+spec: {}

examples/gateway-api/nginx.yaml

@@ -0,0 +1,61 @@
+apiVersion: gateway.networking.k8s.io/v1
+kind: HTTPRoute
+metadata:
+  name: nginx
+  namespace: default
+  labels:
+    app: nginx
+spec:
+  hostnames:
+  - nginx-test-app.eu1.netbird.services
+  parentRefs:
+  - name: netbird
+    namespace: netbird
+  rules:
+    - backendRefs:
+        - name: nginx
+          port: 80
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: nginx
+  namespace: default
+  labels:
+    app: nginx
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: nginx
+  strategy:
+    rollingUpdate:
+      maxSurge: 25%
+      maxUnavailable: 25%
+    type: RollingUpdate
+  template:
+    metadata:
+      labels:
+        app: nginx
+    spec:
+      containers:
+      - image: nginx
+        imagePullPolicy: Always
+        name: nginx
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: nginx
+  namespace: default
+  labels:
+    app: nginx
+spec:
+  type: ClusterIP
+  ports:
+  - name: http
+    port: 80
+    protocol: TCP
+    targetPort: 80
+  selector:
+    app: nginx