add Contributing.md
add Contributing.md

ccapndave/superagent,KuroGuo/suberagent,andyburke/superagent,targos/superagent,geminiyellow/superagent,jarvisaoieong/superagent,puterakahfi/superagent,brotchie/superagent,h1bomb/superagent,KuroGuo/suberagent,thejameskyle/superagent,craigspaeth/superagent,deltreey/superagent,soyuka/superagent,andyburke/superagent,geminiyellow/superagent,drinks/superagent,reinaldo13/superagent,philipshurpik/superagent,yussan/superagent,killerlayup/superagent,mvanlonden/superagent-webpack-client,wushuyi/superagent,KingMario/superagent,jarvisaoieong/superagent,stanzi83/superagent,RubenVerborgh/superagent,KingMario/superagent,nemisj/superagent,noikiy/suberagent,modulexcite/superagent,stasha/superagent,yeatszhang/superagent,simonvizzini/superagent,aaroncrows/superagent,focusaurus/superagent,visionmedia/superagent,fredigato/superagent,ertrzyiks/superagent,soyuka/superagent,alinz/superagent,RubenVerborgh/superagent,sebastianvera/superagent,simonvizzini/superagent,targos/superagent,fredigato/superagent,yussan/superagent,craigspaeth/superagent,yeatszhang/superagent,noikiy/suberagent,brainbytes/superagent,kmalakoff/superagent-ls,killerlayup/superagent,ccapndave/superagent,sutoiku/superagent,focusaurus/superagent,h1bomb/superagent,eligolding/superagent,stasha/superagent,alinz/superagent,reinaldo13/superagent,modulexcite/superagent,zsh2938/superagent,sebastianvera/superagent,thejameskyle/superagent,puterakahfi/superagent,stanzi83/superagent,visionmedia/superagent,ertrzyiks/superagent,sutoiku/superagent,nemisj/superagent,mvanlonden/superagent-webpack-client,philipshurpik/superagent,brotchie/superagent,eligolding/superagent,zsh2938/superagent,wushuyi/superagent,aaroncrows/superagent,drinks/superagent,visionmedia/superagent,deltreey/superagent,brainbytes/superagent,kmalakoff/superagent-ls