Add missing Flow tags

.eslintrc

@@ -1,9 +1,16 @@
 {
     "parser": "babel-eslint",
     "plugins": [
+        "flowtype",
         "prettier"
     ],
     "rules": {
+        "flowtype/boolean-style": [
+            2,
+            "boolean"
+        ],
+        "flowtype/no-weak-types": 2,
+        "flowtype/delimiter-dangle": 2,
         "prettier/prettier": ["error", {
             "singleQuote": true,
             "bracketSpacing": false,

package.json

@@ -28,7 +28,8 @@
     "babel-preset-flow": "6.23.0",
     "base64-arraybuffer": "0.1.5",
     "eslint": "4.2.0",
-    "eslint-plugin-prettier": "^2.1.2",
+    "eslint-plugin-flowtype": "2.35.0",
+    "eslint-plugin-prettier": "2.1.2",
     "flow-bin": "0.50.0",
     "prettier": "1.5.3",
     "rimraf": "2.6.1",

src/BezierCurve.js

@@ -1,3 +1,5 @@
+/* @flow */
+'use strict';
 import Vector from './Vector';
 
 export default class BezierCurve {

src/Feature.js

@@ -1,3 +1,6 @@
+/* @flow */
+'use strict';
+
 const testRangeBounds = document => {
     const TEST_HEIGHT = 123;
 
@@ -23,6 +26,7 @@ const testRangeBounds = document => {
 };
 
 const FEATURES = {
+    // $FlowFixMe - get/set properties not yet supported
     get SUPPORT_RANGE_BOUNDS() {
         'use strict';
         const value = testRangeBounds(document);

src/Logger.js

@@ -8,6 +8,7 @@ export default class Logger {
         this.start = Date.now();
     }
 
+    // eslint-disable-next-line flowtype/no-weak-types
     log(...args: any) {
         Function.prototype.bind
             .call(window.console.log, window.console)

src/index.js

@@ -10,7 +10,6 @@ import Color from './Color';
 export type Options = {
     async: boolean,
     imageTimeout: number,
-    renderer: Function,
     proxy: string,
     canvas: HTMLCanvasElement,
     allowTaint: true