i did some research, while you can directly 'edit', its not possible to 'add/delete' from GitHub.. you're technically suppose to manage this GIT thing via the command line 'git' and learn a bunch of the commands to do so..
anyway, taking this a step further, I invited you to this:
https://c9.io/convivea/bit-che-2-scriptsbasically, its an online IDE with GIT support for GitHub. So, once you have an idea of how to 'git pull', 'git add', 'git rm', 'git commit', 'git push'.. etc, then yes, its possible to create a new file online, edit it, and push to the GitHub (which then syncs to the convivea default script pack automatically).
its a little bit scary, and while I'm learning Git, i hit a few wrong commands. but the only changes made to the site are what happen after you 'git commit' and then 'git push', so I was able to do the commands that wipe out my local changes and start again after pulling the latest version 'git pull'...
meh, it works, its a little more technical than i was hoping.
not sure if there are any other online Git editors 'for dummys'