upgrade FlatQueue for faster kNN, close #27

Author: mourner

package.json

@@ -48,11 +48,11 @@
     "esm": "^3.2.25",
     "rbush": "^3.0.1",
     "rbush-knn": "^2.1.0",
-    "rollup": "^2.0.6",
+    "rollup": "^2.1.0",
     "rollup-plugin-terser": "^5.3.0",
     "tape": "^4.13.2"
   },
   "dependencies": {
-    "flatqueue": "^1.1.0"
+    "flatqueue": "^1.2.0"
   }
 }