Update README.md - cosmetic
Update README.md - cosmetic

Split up the To-Do section into 2 sections :

 - Add Functionality - new features that are to be added to the script.
 - Internal refactoring - improvements to the code not visible to the user

Signed-off-by: Grant Ramsay <4ab1b2fdb7784a8f9b55e81e3261617f44fd0585@gmail.com>

seapagan/update_repo,seapagan/update_repo,seapagan/update_repo,seapagan/update_repo