Fix release date

Bump version

Releasing 1.6.7.

Releasing 1.6.6, with one critical bugfix.

Releasing bugfixes and a speed regression fix.

Releasing 1.6.4, with localization features and some polish.

Changing version numbers, preparing for release

Preparing for version 1.6.2

Preparing for version 1.6.1

Preparing for 1.6.0 release