Improve the output of help, prompts, and so on for `databricks bundle
init` and the default template.
Among other things, this PR adds support for a new `welcome_message`
property that lets a template print a custom message on success:
```
$ databricks bundle init
Template to use [default-python]:
Unique name for this project [my_project]: lennart_project
Include a stub (sample) notebook in 'lennart_project/src': yes
Include a stub (sample) Delta Live Tables pipeline in 'lennart_project/src': yes
Include a stub (sample) Python package in 'lennart_project/src': yes
✨ Your new project has been created in the 'lennart_project' directory!
Please refer to the README.md of your project for further instructions on getting started.
Or read the documentation on Databricks Asset Bundles at https://docs.databricks.com/dev-tools/bundles/index.html.
```
---------
Co-authored-by: shreyas-goenka <88374338+shreyas-goenka@users.noreply.github.com>
## Changes
At a high level this PR adds new schema validation and moves
functionality that should be present in the jsonschema package, but
resides in the template package today, to the jsonschema package. This
includes for example schema validation, schema instance validation, to /
from string conversion methods etc.
The list below outlines all the pieces that have been moved over, and
the new validation bits added.
This PR:
1. Adds casting default value of schema properties to integers to the
jsonschema.Load method.
2. Adds validation for default value types for schema properties,
checking they are consistant with the type defined.
3. Introduces the LoadInstance and ValidateInstance methods to the json
schema package. These methods can be used to read and validate JSON
documents against the schema.
4. Replaces validation done for template inputs to use the newly defined
JSON schema validation functions.
5. Moves to/from string and isInteger utility methods to the json schema
package.
## Tests
Existing and new unit tests.
Lennart Kats (databricks)
shreyas-goenka