Update readme for file explorer changes

README.md

@@ -10,6 +10,7 @@
 
 - File Explorer
   - Back, Forward, Recent locations, Up one level, Address bar, Search
+  - Thumbnail & Details Views
 - [Drag & Drop](https://developer.mozilla.org/en-US/docs/Web/API/HTML_Drag_and_Drop_API) File Support (internal & external)
   - Loading progress dialog
 - ZIP ([write support](https://www.npmjs.com/package/fflate)), [ZIP](https://github.com/jvilk/BrowserFS/blob/master/src/backends/ZipFS.ts)/[ISO](https://github.com/jvilk/BrowserFS/blob/master/src/backends/IsoFS.ts) read support, [7Z/GZ/RAR/TAR/etc. extract](https://github.com/use-strict/7z-wasm) support