Update Docstrings api for documentation (issue #893)

[manuelhsantana]

This PR introduces a comprehensive update to our documentation with the addition of an OpenFL API section. This section provides detailed information about the various components of the OpenFL, enhancing the overall understanding and usability of the platform.

Key updates in this PR include:

1. OpenFL API Section Addition: A dedicated section for OpenFL API has been added to the documentation. This section provides a valuable resource for both new and existing users.
2. Updated Docstrings: We have revised and updated the docstrings throughout the documentation to ensure clarity and consistency. These docstrings now provide more accurate and detailed descriptions of the functions and methods, facilitating better understanding and usage.
3. The docstrings for the following modules have been updated:

• Component
• Cryptography
• Databases (TensorDB)
• Experimental
• Federated
• Interface
• Native
• Pipelines
• Plugins
• Protocols
• Transport
• Utilities

The updated docstrings provide a more detailed explanation of these components, enhancing the user's understanding of their functions and roles within the OpenFL.

4. Addition of Indexes and Tables: To improve the navigability and accessibility of the documentation, we have added indexes and tables where necessary. These additions will make it easier for users to find the information they need.

This PR is a significant step towards improving the quality and comprehensibility of our documentation. We believe that these updates will greatly enhance the user experience and make it easier for users to understand and utilize OpenFL.