Update README's Repo structure diagram (e.g., incorrectly lists "openwhisk-swift")

## Environment details:

* local deployment, vagrant, native ubuntu, Mac OS, Bluemix, ...
* version of docker, vagrant, ubuntu, ...

## Steps to reproduce the issue:

1. View README

## Provide the expected results and outputs:

```
Fix diagram to remove "openwhisk-swift" as a project repo.
```

## Provide the actual results and outputs:

```
N/A
```

## Additional information you deem important:
* issue happens only occasionally or under certain circumstances
* changes you did or observed in the environment