removes all non-alphanumeric chars from slug
removes all non-alphanumeric chars from slug
mdavid/fixdemocracyfirst,bev-a-tron/fixdemocracyfirst,Lessig2016/fixdemocracyfirst,mdavid/fixdemocracyfirst,bev-a-tron/fixdemocracyfirst,bev-a-tron/fixdemocracyfirst,mdavid/fixdemocracyfirst,bev-a-tron/fixdemocracyfirst,Lessig2016/fixdemocracyfirst,mdavid/fixdemocracyfirst,Lessig2016/fixdemocracyfirst,Lessig2016/fixdemocracyfirst