Implemented a few basic unit tests

Jenkinsfile

@@ -55,6 +55,29 @@ pipeline {
         }
       }
     }
+    stage('Test') {
+      agent {
+          docker {
+              image "rightbrainnetworks/auto-semver:${env.VERSION}"
+          }
+      }
+      steps
+      {
+        dir('semver')
+        {
+          sh 'python tests.py'
+        }
+      }
+      post{
+        // Update Git with status of test stage.
+        success {
+          updateGithubCommitStatus(GITHUB_URL, 'Passed test stage', 'SUCCESS', 'Test')
+        }
+        failure {
+          updateGithubCommitStatus(GITHUB_URL, 'Failed test stage', 'FAILURE', 'Test')
+        }
+      }
+    }
     stage('Push')
     {
       steps {