Try to restore the previously opened buffer when converting to client mode
Try to restore the previously opened buffer when converting to client mode

Fixes #483

occivink/kakoune,lenormf/kakoune,alexherbo2/kakoune,jjthrash/kakoune,ekie/kakoune,danr/kakoune,occivink/kakoune,danr/kakoune,Somasis/kakoune,danr/kakoune,jjthrash/kakoune,alexherbo2/kakoune,jkonecny12/kakoune,Somasis/kakoune,alexherbo2/kakoune,mawww/kakoune,ekie/kakoune,casimir/kakoune,flavius/kakoune,lenormf/kakoune,mawww/kakoune,ekie/kakoune,occivink/kakoune,casimir/kakoune,occivink/kakoune,jkonecny12/kakoune,Somasis/kakoune,Somasis/kakoune,mawww/kakoune,jjthrash/kakoune,alexherbo2/kakoune,jjthrash/kakoune,lenormf/kakoune,flavius/kakoune,ekie/kakoune,jkonecny12/kakoune,flavius/kakoune,flavius/kakoune,casimir/kakoune,casimir/kakoune,jkonecny12/kakoune,mawww/kakoune,danr/kakoune,lenormf/kakoune