Merge pull request DP-3T#115 from seguri/patch-1

Update README.md to remove repetition of "privacy preserving"

README.md

@@ -1,6 +1,6 @@
 # Decentralized Privacy-Preserving Proximity Tracing
 
-This repository contains a proposal for a secure and privacy-preserving decentralized privacy-preserving proximity tracing system. Its goal is to simplify and accelerate the process of identifying people who have been in contact with an infected person, thus providing a technological foundation to help slow the spread of the SARS-CoV-2 virus. The system aims to minimise privacy and security risks for individuals and communities and guarantee the highest level of data protection.
+This repository contains a proposal for a secure and decentralized privacy-preserving proximity tracing system. Its goal is to simplify and accelerate the process of identifying people who have been in contact with an infected person, thus providing a technological foundation to help slow the spread of the SARS-CoV-2 virus. The system aims to minimise privacy and security risks for individuals and communities and guarantee the highest level of data protection.
 
 By publishing this document we seek feedback from a broad audience on the high-level design, its security and privacy properties, and the functionality it offers; so that further protection mechanisms can be added if weaknesses are identified. The [white paper document](DP3T%20White%20Paper.pdf) is accompanied by an [overview of the data protection aspects of the design](DP3T%20-%20Data%20Protection%20and%20Security.pdf), and a [three page simplified introduction to the protocol](DP3T%20-%20Simplified%20Three%20Page%20Brief.pdf).