Merge branch 'master' of github.com:sequelize/sequelize
Added dirty tracking
Added helper method for checking change (incl. Date and empty values), fixed some small stuff and added more tests
Renamed areChanged to didChange and added support for underscore in setter
Merge branch 'master' of github.com:sequelize/sequelize
Merge branch 'dirty-tracking' of https://github.com/mstorgaard/sequelize into mstorgaard-dirty-tracking
renamed didChange to hasChanged
Merge branch 'mstorgaard-dirty-tracking'