- Module.exports now exports the TaskGroup class, of which `Task` and `TaskGroup` are now children
- Added `Task` attribute on the TaskGroup class to allow over-riding of what should be the sub-task class
- Added `TaskGroup` attribute on the TaskGroup class to allow over-riding of what should be the sub-taskgroup class
- Added the `sync` configuration option, which when set to `true` will allow the execution of a Task or TaskGroup to execute synchronously
- Updated dependencies