Add .travis.yml

For running the newly added syntax_checker + PEP8 test
for the Python files in this project.

Also added small print to syntax_checker to indicate tests passed
successfully (yes, lack of error is also indication but this is
more user friendly imho).

tests/syntax_checker.py

@@ -110,3 +110,4 @@ def check_summary_tag(file_list):
 if __name__ == '__main__':
     check_details_tag(file_list)
     check_summary_tag(file_list)
+    print("tests passed successfully")