## Changes
With this PR, all of the command below print version and exit:
```
$ databricks -v
Databricks CLI v0.100.1-dev+4d3fa76
$ databricks --version
Databricks CLI v0.100.1-dev+4d3fa76
$ databricks version
Databricks CLI v0.100.1-dev+4d3fa76
```
## Tests
Added integration test for each flag or command.