Add contribution note to readme
Add contribution note to readme

nodeonly/bookshelf,stonegithubs/bookshelf,jadengore/bookshelf,lanetix/bookshelf,VideoAmp/bookshelf,vellotis/bookshelf,mdboop/bookshelf,apla/bookshelf,lanetix/bookshelf,tbutman/bookshelf,joshturn/bookshelf,stridentbean/bookshelf,zubeio/bookshelf,nodeonly/bookshelf,dougshamoo/bookshelf,TNuzzi/bookshelf,rbong/bookshelf,skevy/bookshelf,princesust/bookshelf,tbutman/bookshelf,sxhao/bookshelf,shaunstanislaus/bookshelf,tjwudi/bookshelf,tjwudi/bookshelf,offlinehacker/bookshelf,skevy/bookshelf,princesust/bookshelf,vellotis/bookshelf,mdboop/bookshelf,sanchesic89/bookshelf,zdespolit/bookshelf,chrisbroome/bookshelf,rbong/bookshelf,tjwudi/bookshelf,chuym/bookshelf,patbenatar/bookshelf,tgriesser/bookshelf,joshturn/bookshelf,patbenatar/bookshelf,jordansexton/bookshelf,nodeonly/bookshelf,offlinehacker/bookshelf,cspotcode/bookshelf,jadengore/bookshelf,seegno-forks/bookshelf,princesust/bookshelf,seegno-forks/bookshelf,zdespolit/bookshelf,sanchesic89/bookshelf,offlinehacker/bookshelf,apla/bookshelf,cspotcode/bookshelf,stridentbean/bookshelf,zubeio/bookshelf,shaunstanislaus/bookshelf,dougshamoo/bookshelf,mdboop/bookshelf,bookshelf/bookshelf,VideoAmp/bookshelf,patbenatar/bookshelf,shadedprofit/bookshelf,stonegithubs/bookshelf,MadcapJake/bookshelf,joshturn/bookshelf,zdespolit/bookshelf,stonegithubs/bookshelf,dougshamoo/bookshelf,chrisbroome/bookshelf,vellotis/bookshelf,TinOo512/bookshelf,sxhao/bookshelf,stridentbean/bookshelf,bookshelf/bookshelf,tbutman/bookshelf,zubeio/bookshelf,TNuzzi/bookshelf,TNuzzi/bookshelf,sanchesic89/bookshelf,jordansexton/bookshelf,MadcapJake/bookshelf,jadengore/bookshelf,lanetix/bookshelf,shadedprofit/bookshelf,sxhao/bookshelf,VideoAmp/bookshelf,chuym/bookshelf,shadedprofit/bookshelf,tgriesser/bookshelf,skevy/bookshelf,shaunstanislaus/bookshelf,TinOo512/bookshelf,chuym/bookshelf,MadcapJake/bookshelf