Set best practice defaults for network router deployment (#214)

This change sets some Kubernetes best practices as defaults. Such as
topology spread and pod disruption budget.

It also exposes log level and image settings in the root struct to make
it easier to override commonly configured settings.

Fixes #77 
Fixes #162

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

api/v1alpha1/networkrouter_types.go

@@ -11,6 +11,14 @@ type NetworkRouterSpec struct {
 	// +required
 	DNSZoneRef DNSZoneReference `json:"dnsZoneRef"`
 
+	// Netbird client image.
+	// +optional
+	Image string `json:"image,omitempty"`
+
+	// Log level for Netbird client.
+	// +optional
+	LogLevel string `json:"logLevel,omitempty"`
+
 	// WorkloadOverride contains configuration that will override the default workload.
 	// +optional
 	WorkloadOverride *WorkloadOverride `json:"workloadOverride,omitempty"`
@@ -34,6 +42,8 @@ type WorkloadOverride struct {
 
 	// Replicas sets the amount of client replicas.
 	// +optional
+	// +kubebuilder:default=3
+	// +kubebuilder:validation:Minimum=1
 	Replicas *int32 `json:"replicas"`
 
 	// PodTemplate overrides the pod template.