Use `user-error` for user-level errors
Use `user-error` for user-level errors

For errors that are the result of user interaction rather than
actual bugs in merlin, `user-error` is a more low-key response
(and doesn't enter the debugger with `debug-on-error` set).

Use %s rather than %S for messages to avoid displaying the quotes.

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