Show if tag is a def/ref in the cli

cli/src/tags.rs

@@ -42,9 +42,10 @@ pub fn generate_tags(loader: &Loader, scope: Option<&str>, paths: &[String]) ->
                 let tag = tag?;
                 write!(
                     &mut stdout,
-                    "  {:<8} {:<40}\t{:>9}-{:<9}",
+                    "  {:<8} {:<40}\t [{}] {:>9}-{:<9}",
                     tag.kind,
                     str::from_utf8(&source[tag.name_range]).unwrap_or(""),
+                    if tag.is_definition { "definition" } else { "reference" },
                     tag.span.start,
                     tag.span.end,
                 )?;