Ansible version inconsistency for Ubuntu setup

## Environment details:

* Local Deployment
* Ubuntu 18.04

## Steps to reproduce the issue:

1. View documentation & scripts

## Provide the expected results and outputs:

I was trying to deploy OpenWhisk using ansible for the first time on Ubuntu 18.04. However, the setup was confusing due to conflicting documentation/scripts.

On the ansible page, it specifies versions:
```
sudo pip install ansible==4.1.0
sudo pip install jinja2==3.0.1
```
However, these are not the version that are installed as part of the [Ubuntu setup scripts](https://github.com/apache/openwhisk/tree/master/tools/ubuntu-setup). The versions there are significantly older:
```
sudo pip install ansible==2.5.2
sudo pip install jinja2==2.9.6
```

I'd be happy to try updating the Ubuntu Setup scripts, however I wanted to ask first if there was a reason for using the older versions of ansible and jinja?

Also, is there any desire for updating for Ubuntu 20.04/python3?