add types to useCookie hook

added strict types fixes #291 with help and reference of microsoft/TypeScript#20965 (comment)

packages/react-cookie/src/useCookies.tsx

@@ -2,12 +2,12 @@ import { useContext, useEffect, useState, useRef, useMemo } from 'react';
 import { Cookie, CookieSetOptions } from 'universal-cookie';
 import CookiesContext from './CookiesContext';
 
-export default function useCookies(
-  dependencies?: string[]
+export default function useCookies<T extends string, U = {[K in T]?: string}>(
+  dependencies?: T[]
 ): [
-  { [name: string]: any },
-  (name: string, value: Cookie, options?: CookieSetOptions) => void,
-  (name: string, options?: CookieSetOptions) => void
+  U,
+  (name: T, value: Cookie, options?: CookieSetOptions) => void,
+  (name: T, options?: CookieSetOptions) => void
 ] {
   const cookies = useContext(CookiesContext);
   if (!cookies) {
@@ -23,7 +23,7 @@ export default function useCookies(
       const newCookies = cookies.getAll();
 
       if (
-        shouldUpdate(
+        shouldUpdate<T|null,U>(
           dependencies || null,
           newCookies,
           previousCookiesRef.current
@@ -48,10 +48,10 @@ export default function useCookies(
   return [allCookies, setCookie, removeCookie];
 }
 
-function shouldUpdate(
-  dependencies: string[] | null,
-  newCookies: { [name: string]: any },
-  oldCookies: { [name: string]: any }
+function shouldUpdate<T extends string, U = {[K in T]?: string}>(
+  dependencies: T[] | null,
+  newCookies: U,
+  oldCookies: U
 ) {
   if (!dependencies) {
     return true;