[Hyperopt] Create Hyperopt JSONSchema

[arnavgarg1]

When we create a new LudwigModel object, we validate the config schema before allowing train/evaluate/predict, etc. One thing that is missing from our schema check is a way to validate the hyperopt section of the config.

An ideal solution would be to add a function to return a jsonschema object for hyperopt and validate the fields as part of this initial validation check.

Relevant files:

• api.py
• ludwig > schema > __init__.py
• ludwig > hyperopt > run.py

TODOs:

• [ ] Make sure feature types are defined for input and output feature types (see this thread)