doc: update readme

README.md

@@ -44,9 +44,9 @@ Start-BitsTransfer -Source https://raw.githubusercontent.com/rust-lang/rustlings
 
 To install Rustlings. Same as on MacOS/Linux, you will have access to the `rustlings` command after it.
 
-When you get a permission denied message then you have to exclude the directory where you placed the rustlings in your virus-scanner
+If you get a permission denied message, you might have to exclude the directory where you cloned Rustlings in your antivirus.
 
-## Browser:
+## Browser
 
 [Run on Repl.it](https://repl.it/github/rust-lang/rustlings)
 
@@ -150,24 +150,6 @@ cargo uninstall rustlings
 
 Now you should be done!
 
-## Completion
-
-Rustlings isn't done; there are a couple of sections that are very experimental and don't have proper documentation. These include:
-
-- Errors (`exercises/errors/`)
-- Option (`exercises/option/`)
-- Result (`exercises/result/`)
-- Move Semantics (could still be improved, `exercises/move_semantics/`)
-
-Additionally, we could use exercises on a couple of topics:
-
-- Structs
-- Better ownership stuff
-- `impl`
-- ??? probably more
-
-If you are interested in improving or adding new ones, please feel free to contribute! Read on for more information :)
-
 ## Contributing
 
 See [CONTRIBUTING.md](./CONTRIBUTING.md).