Add missing shell expansion variable documentation
Add missing shell expansion variable documentation

Add  a documentation entry for kak_cursor_byte_offset
occivink/kakoune,ekie/kakoune,jkonecny12/kakoune,Somasis/kakoune,lenormf/kakoune,ekie/kakoune,mawww/kakoune,lenormf/kakoune,casimir/kakoune,jjthrash/kakoune,alexherbo2/kakoune,Somasis/kakoune,ekie/kakoune,jkonecny12/kakoune,occivink/kakoune,danr/kakoune,casimir/kakoune,danr/kakoune,jkonecny12/kakoune,jjthrash/kakoune,mawww/kakoune,mawww/kakoune,alexherbo2/kakoune,mawww/kakoune,jkonecny12/kakoune,occivink/kakoune,occivink/kakoune,alexherbo2/kakoune,lenormf/kakoune,danr/kakoune,casimir/kakoune,jjthrash/kakoune,alexherbo2/kakoune,ekie/kakoune,Somasis/kakoune,danr/kakoune,lenormf/kakoune,casimir/kakoune,Somasis/kakoune,jjthrash/kakoune