Issue OData#560 : Unnecessary casts in expression when querying prope…

…rties of the base class for the inheritor

Add E2E xUnit Runner extension to Nuget

Need to resolve public Api review comments OData#460

Upgrade version to 6.0.0-alpha1

Add E2E Test for DynamicProperty Issue OData#330 PR OData#350

Revert the related fix in 5.5.0

Allow enum properties to be keys. OData#138

Fix Build Issues for TFS Build

Add `ModelMetadata.HtmlEncode` property

- use new `ModelMetadata.HtmlEncode` property in HTML helpers
 - conditionally in default HTML display and editor object templates (e.g.
   `@Html.DisplayFor()`) when value is non-null and the template is invoked
   with template depth greater than 1
 - unconditionally in `@Html.DisplayText()` and `@Html.DisplayTextFor()`