Update New flag and last save timestamp on buffer rename
Update New flag and last save timestamp on buffer rename

Fxies #3244

alexherbo2/kakoune,danr/kakoune,alexherbo2/kakoune,casimir/kakoune,Somasis/kakoune,occivink/kakoune,jkonecny12/kakoune,alexherbo2/kakoune,occivink/kakoune,alexherbo2/kakoune,danr/kakoune,danr/kakoune,mawww/kakoune,lenormf/kakoune,mawww/kakoune,mawww/kakoune,casimir/kakoune,jkonecny12/kakoune,Somasis/kakoune,Somasis/kakoune,casimir/kakoune,lenormf/kakoune,jkonecny12/kakoune,casimir/kakoune,occivink/kakoune,occivink/kakoune,mawww/kakoune,danr/kakoune,jkonecny12/kakoune,Somasis/kakoune,lenormf/kakoune,lenormf/kakoune