Integration tests: split up Docker setup, move docker_compose tests into own group (#718)

* Rename setup role.

* Create new CI group 6, and move docker_compose v1 tests into there.

* Split up Docker setup in integration tests.

* Change setup_docker_compose_v1 to install its own Docker SDK for Python.

* Docker SDK for Python not needed to set up registry or query host info.

.azure-pipelines/azure-pipelines.yml

@@ -120,6 +120,7 @@ stages:
           groups:
             - 4
             - 5
+            - 6
   - stage: Docker_2_16
     displayName: Docker 2.16
     dependsOn: []
@@ -137,6 +138,7 @@ stages:
           groups:
             - 4
             - 5
+            - 6
   - stage: Docker_2_15
     displayName: Docker 2.15
     dependsOn: []
@@ -152,6 +154,7 @@ stages:
           groups:
             - 4
             - 5
+            - 6
   - stage: Docker_2_14
     displayName: Docker 2.14
     dependsOn: []
@@ -165,6 +168,7 @@ stages:
           groups:
             - 4
             - 5
+            - 6
 
 ### Community Docker
   - stage: Docker_community_devel
@@ -184,6 +188,7 @@ stages:
           groups:
             - 4
             - 5
+            - 6
 
 ### Remote
   - stage: Remote_devel
@@ -205,6 +210,7 @@ stages:
             - 3
             - 4
             - 5
+            - 6
   - stage: Remote_2_16
     displayName: Remote 2.16
     dependsOn: []