Update about.md
Update about.md

changing as per Erin's list
datacarpentry/datacarpentry.github.io,ErinBecker/datacarpentry.github.io,ErinBecker/datacarpentry.github.io,datacarpentry/datacarpentry.github.io,ErinBecker/datacarpentry.github.io,ErinBecker/datacarpentry.github.io,datacarpentry/datacarpentry.github.io