trying travis tests in parallel

.travis.yml

@@ -1,27 +1,11 @@
-jobs:
-  include:
-    - stage: xenial and Postgres 10.1
-      sudo: required
-      dist: xenial
-      language: generic
+sudo: required
 
-      services:
-        - docker
+services:
+  - docker
 
-      before_install:
-        - docker pull cartoimages/engine-xenial-pg101
+before_install:
+  - docker pull cartoimages/engine-xenial-pg101
+  - docker pull cartoimages/engine-xenial-pg95
 
-      script: docker run -e POSTGIS_VERSION=2.4 -v `pwd`:/srv cartoimages/engine-xenial-pg101 bash run_tests_docker.sh
-
-    - stage: xenial and Postgres 9.5
-      sudo: required
-      dist: xenial
-      language: generic
-
-      services:
-        - docker
-
-      before_install:
-        - docker pull cartoimages/engine-xenial-pg95
-
-      script: docker run -e POSTGIS_VERSION=2.4 -v `pwd`:/srv cartoimages/engine-xenial-pg95 bash run_tests_docker.sh
+script: docker run -e POSTGIS_VERSION=2.4 -v `pwd`:/srv cartoimages/engine-xenial-pg101 bash run_tests_docker.sh
+script: docker run -e POSTGIS_VERSION=2.4 -v `pwd`:/srv cartoimages/engine-xenial-pg95 bash run_tests_docker.sh