Regex: Make the Split op only take a single offset parameter
Regex: Make the Split op only take a single offset parameter

Split now creates a new thread and keep the current one running, as
all of its uses are compatible with this behaviour, which enable a
more compact compiled code.

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