remove functions related to best header

src/index.rs

@@ -297,11 +297,6 @@ impl Index {
         *headers = read_indexed_headers(store);
     }
 
-    pub fn best_header(&self) -> Option<HeaderEntry> {
-        let headers = self.headers.read().unwrap();
-        headers.header_by_blockhash(&headers.tip()).cloned()
-    }
-
     pub fn get_header(&self, height: usize) -> Option<HeaderEntry> {
         self.headers
             .read()

src/query.rs

@@ -303,11 +303,6 @@ impl Query {
         })
     }
 
-    pub fn get_best_header(&self) -> Result<HeaderEntry> {
-        let last_header = self.app.index().best_header();
-        Ok(last_header.chain_err(|| "no headers indexed")?.clone())
-    }
-
     pub fn update_mempool(&self) -> Result<()> {
         self.tracker.write().unwrap().update(self.app.daemon())
     }