Systemd units, limits, and bin path fixes

* Add restart for weave service unit
* Reuse docker_bin_dir everythere
* Limit systemd managed docker containers by CPU/RAM. Do not configure native
  systemd limits due to the lack of consensus in the kernel community
  requires out-of-tree kernel patches.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

roles/kubernetes-apps/ansible/templates/calico-policy-controller.yml.j2

@@ -25,6 +25,13 @@ spec:
         - name: calico-policy-controller
           image: {{ calico_policy_image_repo }}:{{ calico_policy_image_tag }}
           imagePullPolicy: {{ k8s_image_pull_policy }}
+          resources:
+            limits:
+              cpu: {{ calico_policy_controller_cpu_limit }}
+              memory: {{ calico_policy_controller_memory_limit }}
+            requests:
+              cpu: {{ calico_policy_controller_cpu_requests }}
+              memory: {{ calico_policy_controller_memory_requests }}
           env:
             - name: ETCD_ENDPOINTS
               value: "{{ etcd_access_endpoint }}"