Update README.md file according to README.md template

Configuration section is missing as it is required field as per the readme.md file template.

Reviewed ckeditor.patch, the patch is not cleanly applied.

1. Project name is the first line of the document, and only level one heading (#).
2. Headings capitalized with an initial capital, following standard English sentence rules.
3. Bulleted lists denoted by dashes (-).
4.Headings prefixed with #/##/### to indicate level of heading (h1/h2/h3) followed by a blank line

Addressed the comment #6. Please review.

@sakthi_dev reviewed you patch, however,
Bulleted lists denoted by dashes (-) is still not addressed.
You need to update that in Table of contents section.