Add ability to exclude endpoints from basic auth

[JeremyGibson]

Tequila provides the ability to configure ngnix to exclude defined paths when basic auth is enabled. We need something like this in django-k8s.

The solution below uses an additional ingress controller to allow in the traffic

AC:

• add a list var k8s_container_htpasswd_ignore_paths
• Update web.yaml with code similar to the below example.

The additional ingress controller configured with a list of ignore_paths

---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: "ingress-{{ container["name"] }}-htpasswd-ignore-paths"
  namespace: "{{ k8s_namespace }}"
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.org/mergeable-ingress-type: minion
    nginx.ingress.kubernetes.io/backend-protocol: "{{ container["protocol"] }}"
    nginx.ingress.kubernetes.io/auth-type: ""
{% for key, value in container["ingress_annotations"].items() %}
    {{ key }}: "{{ value }}"
{% endfor %}
{% if k8s_container_htpasswd_ignore_paths | length > 0 %}
spec:
  rules:
{% for domain in k8s_domain_names %}
  - host: "{{ domain }}"
    http:
      paths:
{% for ingress_path in k8s_container_htpasswd_ignore_paths %}
      - path: "{{ ingress_path }}"
        backend:
          serviceName: "{{ container["name"] }}"
          servicePort: {{ container["port"] }}