Clarify autoformatting in readme

[ahmad-reza619]

Describe the bug
I think the readme lacks the description of what autofomatting is. I thought of autoformatting as formatting the plain table or it could mean formatting the number to become like currency for example. Maybe we can state explicitly as to what this plugin autoformat

To Reproduce
Steps to reproduce the behavior:

• Nothing as this is documentation

Expected behavior
I expected the feature of autoformatting to be explained more clearly in the readme.

[tgrosinger]

Please feel free to take a pass at making the README more clear and submitting a pull request.