Replace Jenkinsfile in IKS branch with the one from the ICP branch

[odrodrig]

As a developer, I would like to use the Jenkinsfile to create a kubernetes deployment so that I can deploy to IKS rather than just create docker containers on Play With Docker. The Jenkins file in the icp branch should work.

• The jenkinsfile creates a new deployment if non exists
• The jenkinsfile updates the deployment if one exists
• The jenkinsfile is able to authenticate with the user's DockerHub account
• The jenkinsfile is documented