Silence warning

src/api4/binned.rs

@@ -1,6 +1,5 @@
 use crate::transform::TransformQuery;
 use netpod::get_url_query_pairs;
-use netpod::log;
 use netpod::log::*;
 use netpod::query::CacheUsage;
 use netpod::range::evrange::SeriesRange;
@@ -71,6 +70,7 @@ mod serde_option_vec_duration {
     }
 }
 
+#[allow(unused)]
 fn vec_is_empty<T>(x: &Vec<T>) -> bool {
     x.len() == 0
 }