Add Ubuntu 20.04 installation instruction (#681)

README.md

@@ -46,6 +46,24 @@ python3 -m pip install bluepy
 python3 rsf.py
 ```
 
+## Installation on Ubuntu 20.04
+
+```
+sudo apt-get install git python3-pip
+git clone https://github.com/threat9/routersploit
+cd routersploit
+python3 -m pip install -r requirements.txt
+python3 rsf.py
+```
+
+Bluetooth Low Enery support:
+
+```
+sudo apt-get install libglib2.0-dev
+python3 -m pip install bluepy
+python3 rsf.py
+```
+
 ## Installation on Ubuntu 18.04 & 17.10
 
 ```