Fix fallback extension section in docs

[rustamwin]

Q	A
Is bugfix?	✔️/❌
New feature?	✔️/❌
Breaks BC?	✔️/❌
Fixed issues	#236

[what-the-diff]

PR Summary

• Enhanced View Rendering
  This change adds new functionality to the way our software renders (displays) views. Earlier, specifying a file extension was mandatory while naming views. We have now implemented a feature that allows views to be named without a file extension, potentially enhancing usability and speeding up workflow.

• New Methods for Fallback Extensions
  We have introduced two new methods: getFallbackExtensions and withFallbackExtension. These can be used to manage these 'fallback' extensions, which will now be used when a view is named without an explicit file extension. The software will choose the first available fallback extension for view rendering.

Overall, these changes should help to streamline the workflow, making it easier to name and manage views in our system.