Update README.md (#1891)

* Update README.md

Hey @norhh, let's please update the README and about section (the one in the top right). Nobody uses Roostock anymore and the MythX Discord no longer offers any support AFAIK.

* Update README.md

README.md

@@ -12,8 +12,7 @@
 [![Pypi Installs](https://static.pepy.tech/badge/mythril)](https://pepy.tech/project/mythril)
 [![DockerHub Pulls](https://img.shields.io/docker/pulls/mythril/myth.svg)](https://cloud.docker.com/u/mythril/repository/docker/mythril/myth)
 
-Mythril is a security analysis tool for EVM bytecode. It detects security vulnerabilities in smart contracts built for Ethereum, Hedera, Quorum, Vechain, Rootstock, Tron and other EVM-compatible blockchains. It uses symbolic execution, SMT solving and taint analysis to detect a variety of security vulnerabilities. 
-
+Mythril is a symbolic-execution-based securty analysis tool for EVM bytecode. It detects security vulnerabilities in smart contracts built for Ethereum and other EVM-compatible blockchains.
 
 Whether you want to contribute, need support, or want to learn what we have cooking for the future, you can checkout diligence-mythx channel in [ConsenSys Discord server](https://discord.gg/consensys).