allow non-loggedin users to access public bucket (#5570)

* conditionally render main action buttons

- Make bucket action will be available only for loggedIn users
- File upload button will be avaialble for loggedIn users
  and non-loggedIn users if the prefix is writable

* select the bucket and prefix from the url

When the url contains bucket and prefix, it will be selected
by default instead of the first bucket from the list.

* show BucketSearch only for LoggedIn users

* allow non-LoggedIn users to access public bucket

* removed unused Router imports

* fix test case failures in BucketList.test.js

* remove dupicate minioBrowserPrefix from url

since history is already initialized with minioBrowserPrefix,
no need to use it in push or replace

* remove unused match from App component

* remove unused minioBrowserPrefix imports

browser/app/js/browser/SideBar.js

@@ -25,6 +25,7 @@ import BucketSearch from "../buckets/BucketSearch"
 import BucketList from "../buckets/BucketList"
 import Host from "./Host"
 import * as actionsCommon from "./actions"
+import web from "../web"
 
 export const SideBar = ({ sidebarOpen, clickOutside }) => {
   return (
@@ -40,7 +41,7 @@ export const SideBar = ({ sidebarOpen, clickOutside }) => {
           <h2>Minio Browser</h2>
         </div>
         <div className="fes-list">
-          <BucketSearch />
+          {web.LoggedIn() && <BucketSearch />}
           <BucketList />
         </div>
         <Host />