README: emacs: simplify deps
README: emacs: simplify deps

No need for json.el AFAICS.
fxfactorial/merlin,the-lambda-church/merlin,neojski/merlin,rgrinberg/merlin,chambart/merlin,chambart/merlin,haselwarter/merlin,neojski/merlin,neojski/merlin,haselwarter/merlin,ocaml/merlin,dra27/merlin,chambart/merlin,haselwarter/merlin,fxfactorial/merlin,neojski/merlin,rgrinberg/merlin,dra27/merlin,fxfactorial/merlin,dra27/merlin,fxfactorial/merlin,rgrinberg/merlin,the-lambda-church/merlin,ocaml/merlin,the-lambda-church/merlin,haselwarter/merlin,ocaml/merlin,dra27/merlin,rgrinberg/merlin,chriskonstad/merlin,ocaml/merlin,chriskonstad/merlin,chambart/merlin