all: update the path on serve-doc task

Since the all documentation files has been moved to _doc,
the serve-doc task should watch and serve directory _doc too.

1 files changed, 1 insertions, 1 deletions

diff --git a/Makefile b/Makefile
index 69792b0..1475a97 100644
--- a/Makefile
+++ b/Makefile
@@ -20,4 +20,4 @@ test-parser:
 	go test -v -run=Open .
 
 serve-doc:
-	ciigo serve .
+	ciigo serve _doc/