use a Map instead of an Array for catchers

README.md

@@ -267,6 +267,9 @@ const w = wretcher()
 
 // No need to catch 404 or 500 code, they are already taken care of.
 w.url("http://myapi.com/get/something").get().json(json => /* ... */)
+
+// Default catchers can be overridden if needed.
+w.url("...").notFound(err => /* overrides the default 'redirect' catcher */)
 ```
 
 #### options(options: Object)

dist/resolver.d.ts

@@ -4,7 +4,7 @@ export declare type WretcherError = Error & {
     text?: string;
     json?: any;
 };
-export declare const resolver: (url: any) => (catchers?: any[]) => (opts?: {}) => {
+export declare const resolver: (url: any) => (catchers?: Map<number, (error: WretcherError) => void>) => (opts?: {}) => {
     res: <Result = Response>(cb?: (type: void) => Result) => Promise<Result>;
     json: <Result = {
         [key: string]: any;

dist/wretcher.d.ts

@@ -8,7 +8,7 @@ export declare class Wretcher {
     private _url;
     private _options;
     private _catchers;
-    protected constructor(_url: string, _options?: RequestInit, _catchers?: Array<(error: WretcherError) => void>);
+    protected constructor(_url: string, _options?: RequestInit, _catchers?: Map<number, (error: WretcherError) => void>);
     static factory(url?: string, opts?: RequestInit): Wretcher;
     private selfFactory({url, options, catchers}?);
     /**