Bump version

Fix.

Version bump

Verison bump

New slashing mechanism (paritytech#554)

* Slashing improvements

- unstake when balance too low
- unstake after N slashes according to val prefs
- don't early-terminate session/era unless unstaked
- offline grace period before punishment

* Fix warning

* Cleanups and ensure slash_count decays

* Bump authoring version and introduce needed authoring stub

* Rename

* Fix offline tracker

* Fix offline tracker

* Renames

* Add test

* Tests

* Tests.

Backport Dockerfile to v0.2.x (paritytech#548)

Slashing for voted-offline validators. (paritytech#541)

[Backport] Vote out offline authorities

Bump version.

Version bump

Merge branch 'master' into v0.2