Add note re: participants + elsewhere (#406)
Add note re: participants + elsewhere (#406)

studio666/gratipay.com,bountysource/www.gittip.com,mccolgst/www.gittip.com,gratipay/gratipay.com,MikeFair/www.gittip.com,mccolgst/www.gittip.com,bountysource/www.gittip.com,eXcomm/gratipay.com,studio666/gratipay.com,MikeFair/www.gittip.com,gratipay/gratipay.com,mccolgst/www.gittip.com,studio666/gratipay.com,bountysource/www.gittip.com,gratipay/gratipay.com,gratipay/gratipay.com,mccolgst/www.gittip.com,MikeFair/www.gittip.com,studio666/gratipay.com,eXcomm/gratipay.com,eXcomm/gratipay.com,eXcomm/gratipay.com,bountysource/www.gittip.com