ci: install ansible and ansible-lint in a single command to prevent versions mismatch.

Also install other packages from pip in the same command. This should help us to identify issues
with conflicted dependencies earlier and prevent issues like #1120 and #1148 in future.

Fix #1148

Author: php-coder

.travis.yml

@@ -24,11 +24,7 @@ before_script:
       mkdir -p /tmp/uploads /tmp/preview;
       cp src/main/resources/test/test.png /tmp/uploads/1.png;
       npm install -g bootlint;
-      pip install --user html5validator robotframework-lint;
-      if [ "$TRAVIS_BRANCH" = 'prod' -a "$TRAVIS_PULL_REQUEST" = 'false' ]; then
-        pip install --user ansible==2.1.1.0;
-      fi;
-      pip install --user ansible-lint;
+      pip install --user html5validator robotframework-lint ansible==2.1.1.0 ansible-lint;
       if [ "$TRAVIS_PULL_REQUEST" != 'false' ]; then
         gem install danger nokogiri --no-ri --no-rdoc;
       fi;