HTML validation + Actually associate messages to errors + Fix inverted behavior on new blog and post form

src/routes/comments.rs

@@ -20,7 +20,7 @@ use inbox::Inbox;
 #[derive(FromForm, Debug, Validate)]
 struct NewCommentForm {
     pub responding_to: Option<i32>,
-    #[validate(length(min = "1"))]
+    #[validate(length(min = "1", message = "Your comment can't be empty"))]
     pub content: String
 }