Added privacy roadmap (#1386)

Signed-off-by: Adrian Sutton <adrian.sutton@consensys.net>

PRIVACYROADMAP.MD

@@ -0,0 +1,26 @@
+# Privacy Roadmap
+
+This document provides a more detailed view of the privacy roadmap. Like [the overall roadmap](ROADMAP.md), 
+it is a living document, which will evolve and change over time.  In particular the features in later versions 
+are likely to be refined and change.
+
+We use the approach of  `#now`, `#next`, `#later` [used by foursquare](https://medium.com/@noah_weiss/now-next-later-roadmaps-without-the-drudgery-1cfe65656645), with a slightly different time horizon.  
+Our now scale is about 3 months, next about 6 months, and then later is beyond.
+
+## Now (up to v1.2)
+
+* Privacy group management added to JSON RPC-API
+* Support for external key management 
+
+## Next 
+
+* Ability to add and remove members from privacy groups
+* Many to many relationship between Pantheon nodes and Orion nodes 
+* Privacy group consensus 
+* Cross privacy group communication 
+* On-chain privacy 
+
+## Later
+
+* Sidechains
+

ROADMAP.md

@@ -12,7 +12,7 @@ Our key areas for now are:
 * First Class Client
 
 ### Advanced Privacy
-The current privacy functionality will be enhanced with dynamic privacy groups, including the ability to and remove participants from a privacy group.
+The current privacy functionality will be enhanced as described in the [privacy roadmap](PRIVACYROADMAP.MD).
 
 ### Smart Contract Based Permissioning
 Building on the smart contract based permissioning mechanism implemented in v1.1, additional tooling will be provided through a Dapp to simplify and enhance the interaction with the smart contracts. Permissioning for Ethereum accounts will also be introduced.