feat(travel.resolver): Adding sample code and unittest

App/travel_resolver/libs/sample/greeter.py

@@ -0,0 +1,7 @@
+class GreeterHelper():
+    def __init__(self):
+        self._base_message = "Hello ! "
+
+    def Greet(self, message):
+        print(self._base_message + message)
+        return "Hello ! " + message

App/travel_resolver/tests/sample_test.py

@@ -0,0 +1,11 @@
+import unittest
+from travel_resolver.libs.sample.greeter import GreeterHelper
+
+class TestGreeter(unittest.TestCase):
+
+    def setUp(self):
+        self._greeter = GreeterHelper()
+
+    def test_correct_greeting(self):
+        sample_message = "François"
+        self.assertEqual(self._greeter.Greet(sample_message), "Hello ! François")