stdout/stderr control characters aren't properly escaped #5
Description
stdout and stderr are parsed as lossy UTF8 and inserted as Value::String(..) exactly as output by the user.
However, if stdout/stderr contains an ASCII control code, langserver doesn't properly escape it, and for now dockherder turns around and throws something like Unable to parse work output: Illegal unquoted character ((CTRL-CHAR, code 14)): has to be escaped using backslash to be included in string value
It looks like we need only wait on serde-rs/json#58 to be merged, or perhaps serde-rs/json#66.