Release v0.12.0

Release 0.11.2

Release v0.10.0

Bump package.json to v0.9.1

Bump package version to 0.9.0

Merge pull request #126 from tjenkinson/fix-undefined-var

Fix some undefined variables and configure eslint

Merge pull request #123 from nicolo-ribaudo/v-implies-u

Acceppt the different `u` features in `v` mode

Merge pull request #122 from nicolo-ribaudo/fix-unicode-refs

Fix parsing of group references in unicode mode