Add python3 compiling of specific modules (#3641)

.travis.yml

@@ -9,6 +9,7 @@ addons:
     packages:
       - python2.4
       - python2.6
+      - python3.5
 install:
   - pip install git+https://github.com/ansible/ansible.git@devel#egg=ansible
   - pip install git+https://github.com/sivel/ansible-testing.git#egg=ansible_testing
@@ -17,6 +18,8 @@ script:
   - python2.4 -m compileall -fq cloud/amazon/_ec2_ami_search.py cloud/amazon/ec2_facts.py
   - python2.6 -m compileall -fq .
   - python2.7 -m compileall -fq .
+  - python3.4 -m compileall -fq system/ping.py
+  - python3.5 -m compileall -fq system/ping.py
   - ansible-validate-modules --exclude 'utilities/' .
     #- ansible-validate-modules --exclude 'cloud/amazon/ec2_lc\.py|cloud/amazon/ec2_scaling_policy\.py|cloud/amazon/ec2_scaling_policy\.py|cloud/amazon/ec2_asg\.py|cloud/azure/azure\.py|packaging/os/rhn_register\.py|network/openswitch/ops_template\.py|system/hostname\.py|utilities/' .
   #- ./test-docs.sh core