v8-9: Migrating Views

[LottePitcher]

The main things changed in views:

v8	v9
@inherits Umbraco.Web.Mvc.UmbracoViewPage	@inherits Umbraco.Cms.Web.Common.Views.UmbracoViewPage
@Html.Partial("PartialName")	<partial name="PartialName" />
	or @await Html.PartialAsync("PartialName")
@Html.Partial("PartialName", Model)	<partial name="PartialName" model="Model" />
@RenderSection("Head", required: false)	@await RenderSectionAsync("Head", required: false)

But @RenderBody() is still @RenderBody()!