Update index.html
Update index.html

Small spelling mishap on the first paragraph of the 'How to use' section.
veltman/stateface,stitchfix/stateface,propublica/stateface,Skoks/stateface,propublica/stateface,stitchfix/stateface,Skoks/stateface,veltman/stateface,Skoks/stateface,propublica/stateface,veltman/stateface