Create a demo for an A/B testing example

[michelleN]

This issue encompasses upgrading:

• build a demo application scenario
• update Traffic Split version (v1alpha3) Update TrafficSplit version from v1alphav2 to v1alpha4 #705

Note:
How to handle traffic policy conflicts? Should validations be handled in sdk? Should these validation scenarios be discussed more explicitly with the SMI community?

[michelleN]

blocked on #2368

[shashankram]

We have an example for canary rollouts, which should be pretty similar to A/B test barring the differences between the two strategies.