v2.2.11-beta

Made FileSystemWatcher on MockFileSystem mockable (#409)

* Added set; to MockFileSystem.FileSystemWatcher

* Added FILE_SYSTEM_WATCHER_NOT_IMPLEMENTED_EXCEPTION to StringResources

* Made MockFileSystemWatcherFactory throw NotImplementedException

* Removed MockFileSystemWatcher

* MockFileSystemWatcherFactoryTests now assert exception thrown

* Added MockFileSystem test to assert FileSystemWatcher is assignable

* Elaborated on FILE_SYSTEM_WATCHER_NOT_IMPLEMENTED_EXCEPTION message

* Corrected name of MockFileSystemWatcherFactory test

* Update System.IO.Abstractions.TestingHelpers/Properties/Resources.resx

Co-Authored-By: rkoeninger <rkoeninger@att.net>