vim: Fix format string syntax for compat with py < 2.7
vim: Fix format string syntax for compat with py < 2.7

dra27/merlin,neojski/merlin,the-lambda-church/merlin,dra27/merlin,the-lambda-church/merlin,fxfactorial/merlin,haselwarter/merlin,neojski/merlin,neojski/merlin,dra27/merlin,haselwarter/merlin,ocaml/merlin,chambart/merlin,chriskonstad/merlin,the-lambda-church/merlin,rgrinberg/merlin,haselwarter/merlin,ocaml/merlin,haselwarter/merlin,ocaml/merlin,chambart/merlin,rgrinberg/merlin,rgrinberg/merlin,fxfactorial/merlin,neojski/merlin,fxfactorial/merlin,ocaml/merlin,chriskonstad/merlin,chambart/merlin,chambart/merlin,dra27/merlin,rgrinberg/merlin,fxfactorial/merlin