3.0.0 (Beta 1) - #22

* Changed StateChanged Stream to a single Event broadcaster

Added listenable support to busy status changes

* Updated example app to use new state changes

* Expand ErrorEvent handling options. Allow specific subscribing, and handling internal errors

* Add error handling example to example application

* Added isDirty property. Added factory shorthands for current specific primary property types

* Export CurrentClonable

* Update example view model to use new shorthand factory

* Added calculated isDirty getter to CurrentViewModel

* Add tests for isDirty prop

* Add docs to new BusyStatusChanged event

* Implemented controller. Fixed vm reset not clearing busy status.

* Added CurrentTextController to Example project

* Fix type check on date time controller

* Fix default value, and hash equality assignments and checks

* Updated text field carrot snapback to select text when backspacing on a non-null field

* Fix date time asString when cant be parsed. added tests for other supported types

* Fix issue when resetting view model or using setMultiple manually. add test

* Update example. Added missing test.

* Clean up

* Make example page scrollable

* Add seperate custom and any state change listener

* Add seperate custom and any error event listeners

* Fix issue where lists and maps marked as dirty on initial set.

* Fixed an issue where calling resetAll on the view model behaved differently for lists and maps

* Report prop name and hash on list/map change. report inserted item instead of whole list. added tests

* Optionally allow external / parent widget to handle viewmodel lifecycle.

* Fix issue where setMultiple always issued notifications, even if nothing actually changed.

* Update value equality implementation. This fixes issues with map keys, and odd comparison results. Updated stale test descriptions.

* deprecated math functions on int property (generics were odd since you can't impl num)

* added tests for the new int property functions.

* added tests to cover null scenarios in double property math functions

* Clean up statle documentation

* added current validation state. added additive extension (nonbreaking).

* add docs to new current validation classes. fix docs in view model. export current validation

* add some docs around the _omitted internal variable. added unit tests

* progress on integrating current validation with new current text controller.

* Add option to localize default validation errors

* Add additional docs to the current text controller

* update core web files for example app

* Progress on new space themed example app. added logos. removed old example page

* added flight forms page. redfactored app view model

* added launch missing, map and telemetry examples

* added widget tests

* add third version branding

* Move viewmodels out of widget pages

* clean up

* clean up

* clean up

* add code examples to example app. add link to third version website

* Restructure validation results to produce typed issues. This is to support localization without coupling ui to view models

* Update Readmes

* Change current validation to explicit opt in. Reduces footguns. Update docs and examples.

* clean up example propery initialization

* Clean up validation registration. better support context based localization

* Remove unused mixin. Remove tests

* Tie validation execution to TextFormFields. Added convenience Current text widgets without losing native support

* Added tests for text form field integration

* Update readme

* add convenience setter functions for various properties

* Rename factories on CurrentTextController for consistency

* bump version, generate docs

* Add changelog entry