Validation Summary Styling

[nigelatwell]

Currently the tag helper library does not work with the built in asp mvc validation summary tag helper.
To implement validation summary that matches the version specified in the front end library guidelines we currently have to manually add the styling. i.e. hand code to iterate the Model State errors.
We intend to implement a tag helper that works with validation summary before we release the tag helper library as version 2.3.0.