Update README.md

Author: voter101

README.md

@@ -6,14 +6,12 @@ The Koans are a set of tasks to complete. Prepared tests checks if they are done
 
 ## Installation
 
-Make sure you have Node.js and Python 2 installed.
+Make sure you have Node.js (ver. > 4) and Python 2 installed.
 
   1. `git clone https://github.com/arkency/reactjs_koans.git`
   2. `cd reactjs_koans`
   3. `npm run setup`
 
-Having troubles with installation? Try using Node.js in `0.12` version. You can use [`nvm`](https://github.com/creationix/nvm) to install multiple versions on Node on your machine.
-
 ## Koans structure
 
  * Edit the files found in the **`exercises`** directory.