Create a short description for the Config Split project

Here’s a rough draft description. Thanks @keiserjb for the editing help!

“The configuration split module allows a site to deploy subsets of its configuration to different environments.”

Yes, that was me a second different was removed.

I finally helped out with Project Browser, secondhand though.

Made a slight update to remove the module name from its description, and added an example of why I might use it.

Marked as fixed and credit given

Automatically closed - issue fixed for 2 weeks with no activity.