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).

.travis.yml

@@ -0,0 +1,8 @@
+language: "python"
+python:
+    - "3.8"
+install:
+    - pip install flake8
+script:
+    - flake8 .
+    - python tests/syntax_checker.py

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")