filled in changelog

docs/CHANGELOG.md

 # Eris-DB changelog
 
-## 0.12.0
-
-- Features
-
-
+## 0.12.0-RC3
+This release marks a separation of Eris-DB (the blockchain node of the
+ Eris platform) from our consensus engine Tendermint. This involved 
+ significant refactoring of almost all parts of the code, but provides
+ a solid foundation to build against using future iterations of 
+ Tendermint as well as advanced permissioned smart contract execution.
+ 
+ Many changes are under the hood but here are the main externally 
+ visible changes:
+
+- Features and improvements
+  - Upgrade to Tendermint 0.6.0 in-process consensus
+  - Support DELEGATECALL opcode in Ethereum Virtual Machine (important for solidity library calls)
+  - ARM support
+  - Docker image size reduced
+  - Introduction of eris-client companion library for interacting with
+  eris:db
+  - Improved configuration handling using Viper
+  - Allow multiple event subscriptions from same host under rpv/tendermint
+ 
 - Tool changes  
-  - use glide instead of godeps for dependencies
-
-
-- General Codebase
-  - upgrade to Tendermint 0.6.0
-
-
-- Bugfixes
-
-
+  - Use glide instead of godeps for dependencies
+  
 - Testing
+  - Separation of integration for RPC and unit tests
 
-
-- Documentation
-
-## 0.11.4 - _2016-04-29_
+- Bugfixes
+  - [EVM] Fix calculation of child CALL gaslimit (allowing solidity library calls to work properly)
+  - [RPC/v0] Fix blocking event subscription in transactAndHold (preventing return in Javascript libraries)
+  - [Blockchain] Fix getBlocks to respect block height cap