added note to README explaining s.gif (https://github.com/jakesgordon/sprite-factory/issues/4)
added note to README explaining s.gif (https://github.com/jakesgordon/sprite-factory/issues/4)

manaflask/sprite-factory,strzibny/sprite-factory,jakesgordon/sprite-factory,bastiRe/sprite-factory,bastiRe/sprite-factory,jakesgordon/sprite-factory,strzibny/sprite-factory,manaflask/sprite-factory