Adding Documentation for SparkNLP Readers and Partition class

[paulamib123]

Description

This PR adds documentation and examples for the Partition class and various document readers in spark-nlp.

Motivation and Context

Helps users understand how to use Partition and Readers to read different types of Documents.

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• Code improvements with no or little impact
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING page.
• I have added tests to cover my changes.
• All new and existing tests passed.

[DevinTDHa]

Some long lines need truncation and some minor things but otherwise looks good to me. Thanks!

[DevinTDHa]

can you check if these custom headers render correctly?

[DevinTDHa]

@danilojsl Can you also check if these docs are accurate for your new feature?

[danilojsl]

@paulamib123 Could you please create a new branch based on feature/SPARKNLP-1174-Adding-PartitionTransformer and add your changes there?

I also recommend cloning the original spark-nlp repository directly instead of forking it. This will make it easier for us to review your changes locally and provide more effective feedback.

[DevinTDHa]

@danilojsl thanks for the thorough review!

@paulamib123 I also usually work on my own fork and If you rebase your changes to the newest brach it should be fine as well.

[danilojsl]

@paulamib123 I forgot that the new feature/SPARKNLP-1174-Adding-PartitionTransformer includes the PartitionTransformer annotator, so we'll need to add documentation for it. Please keep that in mind. If you have any questions, don’t hesitate to reach out to me.

[DevinTDHa]

Closing, duplicate of #14581