Update r_configure_gateway_service.md
Update r_configure_gateway_service.md

Polished the new doc for http.proxy, http.keepalive, and http.keepalive.connections
irina-mitrea-luxoft/gateway,mgherghe/gateway,danibusu/gateway,jitsni/gateway,cmebarrow/gateway,a-zuckut/gateway,kaazing/gateway,AdrianCozma/gateway,cmebarrow/gateway,chao-sun-kaazing/gateway,DoruM/gateway,chao-sun-kaazing/gateway,DoruM/gateway,dpwspoon/gateway,justinma246/gateway,justinma246/gateway,kaazing/gateway,jfallows/gateway,veschup/gateway,veschup/gateway,biddyweb/gateway,a-zuckut/gateway,biddyweb/gateway,adrian-galbenus/gateway,kaazing/gateway,cmebarrow/gateway,chao-sun-kaazing/gateway,danibusu/gateway,stanculescu/gateway,stanculescu/gateway,justinma246/gateway,irina-mitrea-luxoft/gateway,jfallows/gateway,jitsni/gateway,DoruM/gateway,dpwspoon/gateway,DoruM/gateway,danibusu/gateway,kaazing/gateway,stanculescu/gateway,Anisotrop/gateway,justinma246/gateway,mgherghe/gateway,jfallows/gateway,AdrianCozma/gateway,nemigaservices/gateway,adrian-galbenus/gateway,cmebarrow/gateway,adrian-galbenus/gateway,jitsni/gateway,nemigaservices/gateway,michaelcretzman/gateway,adrian-galbenus/gateway,a-zuckut/gateway,mjolie/gateway,Anisotrop/gateway,vmaraloiu/gateway,vmaraloiu/gateway,mjolie/gateway,michaelcretzman/gateway,Anisotrop/gateway,veschup/gateway,nemigaservices/gateway,sanjay-saxena/gateway,veschup/gateway,sanjay-saxena/gateway,dpwspoon/gateway,michaelcretzman/gateway,michaelcretzman/gateway,mgherghe/gateway,stanculescu/gateway,mjolie/gateway,irina-mitrea-luxoft/gateway,biddyweb/gateway,a-zuckut/gateway,jfallows/gateway,AdrianCozma/gateway,mgherghe/gateway,danibusu/gateway,mjolie/gateway,vmaraloiu/gateway,irina-mitrea-luxoft/gateway,chao-sun-kaazing/gateway,AdrianCozma/gateway,nemigaservices/gateway,jitsni/gateway,vmaraloiu/gateway,Anisotrop/gateway,dpwspoon/gateway,sanjay-saxena/gateway,biddyweb/gateway,sanjay-saxena/gateway