Add examples and documentation to new I2S library

[VojtechBartoska]

New implementation of I2S library is missing examples and documentation.

To help users to getting started with it, we need to add examples demonstrating the main functions.

Current documentation page of I2S library is describing the old implementation, we need to create a new documentation page for current version. We can keep I2S library docs for v4.4 and create a new page for v3.0.