fix '$' completions for S4 list / data.frames
fix '$' completions for S4 list / data.frames

edrogers/rstudio,john-r-mcpherson/rstudio,JanMarvin/rstudio,jrnold/rstudio,jrnold/rstudio,thklaus/rstudio,edrogers/rstudio,piersharding/rstudio,vbelakov/rstudio,more1/rstudio,githubfun/rstudio,vbelakov/rstudio,john-r-mcpherson/rstudio,more1/rstudio,thklaus/rstudio,jar1karp/rstudio,jrnold/rstudio,john-r-mcpherson/rstudio,brsimioni/rstudio,john-r-mcpherson/rstudio,more1/rstudio,piersharding/rstudio,suribes/rstudio,suribes/rstudio,JanMarvin/rstudio,jzhu8803/rstudio,piersharding/rstudio,edrogers/rstudio,thklaus/rstudio,brsimioni/rstudio,brsimioni/rstudio,piersharding/rstudio,jrnold/rstudio,jar1karp/rstudio,JanMarvin/rstudio,piersharding/rstudio,githubfun/rstudio,piersharding/rstudio,tbarrongh/rstudio,vbelakov/rstudio,jzhu8803/rstudio,more1/rstudio,vbelakov/rstudio,JanMarvin/rstudio,brsimioni/rstudio,tbarrongh/rstudio,githubfun/rstudio,thklaus/rstudio,JanMarvin/rstudio,jrnold/rstudio,thklaus/rstudio,john-r-mcpherson/rstudio,tbarrongh/rstudio,vbelakov/rstudio,JanMarvin/rstudio,suribes/rstudio,vbelakov/rstudio,jzhu8803/rstudio,thklaus/rstudio,jzhu8803/rstudio,githubfun/rstudio,jar1karp/rstudio,piersharding/rstudio,edrogers/rstudio,jrnold/rstudio,piersharding/rstudio,jar1karp/rstudio,jrnold/rstudio,edrogers/rstudio,more1/rstudio,jzhu8803/rstudio,thklaus/rstudio,more1/rstudio,piersharding/rstudio,john-r-mcpherson/rstudio,githubfun/rstudio,edrogers/rstudio,jar1karp/rstudio,suribes/rstudio,tbarrongh/rstudio,jar1karp/rstudio,brsimioni/rstudio,suribes/rstudio,tbarrongh/rstudio,edrogers/rstudio,john-r-mcpherson/rstudio,brsimioni/rstudio,JanMarvin/rstudio,brsimioni/rstudio,tbarrongh/rstudio,githubfun/rstudio,brsimioni/rstudio,jar1karp/rstudio,jar1karp/rstudio,john-r-mcpherson/rstudio,jar1karp/rstudio,suribes/rstudio,JanMarvin/rstudio,tbarrongh/rstudio,jrnold/rstudio,jzhu8803/rstudio,tbarrongh/rstudio,jzhu8803/rstudio,thklaus/rstudio,more1/rstudio,vbelakov/rstudio,edrogers/rstudio,JanMarvin/rstudio,suribes/rstudio,githubfun/rstudio,more1/rstudio,vbelakov/rstudio,suribes/rstudio,jrnold/rstudio,githubfun/rstudio,jzhu8803/rstudio