snap: test: add build and deploy checks (#3330)

* snap: deploy: include review-tools

Enables pre-deployment checks

* snap: build: include snapd

Enables enhanced build-time checks

.travis.yml

@@ -81,6 +81,8 @@ jobs:
      - name: snapcraft
        channel: stable
        confinement: classic
+     - name: review-tools
+       channel: stable
      - name: lxd
        channel: stable
     env:

snap/snapcraft.yaml

@@ -20,6 +20,8 @@ parts:
     plugin: python
     python-packages: [wheel]
     source: .
+    build-snaps:
+    - snapd
     build-packages:
     - git
     - libc-dev