rename 'path_to_string' to a more descriptive name in refactor open
rename 'path_to_string' to a more descriptive name in refactor open

dra27/merlin,the-lambda-church/merlin,dra27/merlin,the-lambda-church/merlin,ocaml/merlin,ocaml/merlin,dra27/merlin,rgrinberg/merlin,dra27/merlin,ocaml/merlin,ocaml/merlin,rgrinberg/merlin,rgrinberg/merlin,the-lambda-church/merlin,rgrinberg/merlin