Clean up under dev index

Author: donnemartin

README.md

@@ -160,10 +160,6 @@ Review the [Contributing Guidelines](https://github.com/donnemartin/system-desig
     * [Powers of two table](#powers-of-two-table)
     * [Latency numbers every programmer should know](#latency-numbers-every-programmer-should-know)
 * [Under development](#under-development)
-    * [Distributed computing](#distributed-computing)
-    * [Consistent hashing](#consistent-hashing)
-    * [Scatter gather](#scatter-gather)
-    * [Contribute](#contributing)
 * [Credits](#credits)
 * [Contact info](#contact-info)
 * [License](#license)