Merge pull request ethereum#279 from ethereum/dev

Release version 2.3.0

Merge pull request ethereum#261 from ethereum/dev

Version bump for master

Merge pull request ethereum#252 from ethereum/dev

Release version v2.1.0

Merge pull request ethereum#206 from ethereum/dev

Internationalisation release

Merge pull request ethereum#196 from ethereum/dev

dev -> master: v1.2.0

Merge pull request ethereum#190 from ethereum/dev

## Release v1.1.1:

* Ensure keystore permissions are 440 ethereum#176
* Adds Prater testnet support ethereum#189
* Removes support for old testnets (Witti, Altona, Medalla, Spadina, Zinken) ethereum#189

Merge pull request ethereum#164 from ethereum/dev

Release v1.1.0 to master

Merge pull request ethereum#145 from ethereum/dev

`dev`->`master`

Merge pull request ethereum#131 from ethereum/v0.4.0-hotfix-version-bump

Bump version number for hotfix release

Merge pull request ethereum#128 from ethereum/dev

dev -> master for Zinken