Update README.md

Add contributors to README
Update avatar settings
Add teambition to corp
Update Google Auth username

Use 'abc' instead of 'abc@gmail.com' as username.
add gitcafe to corp
Hide email

Don't display email in user show page.
Fix teambition url

Change corp teambition url from 'https://teambition.com' to 'https://www.teambition.com'
fix footer's bug

remove padding-bottom of footer
update compiled css

recompile geekon.min.css