- correct file and class names for some HH extensions
- three class names were correct but didn't match containing file
- three class and file names matched but didn't start with HtmlHelper
- clean up trailing whitespace and long lines in changed Extensions.cs files
- `HtmlHelperPartialAsyncExtensions`, `HtmlHelperRenderPartialAsyncExtensions`
and `HtmlHelperValidationExtensions` lacked some `[NotNull]` attributes
- merge extension files by concept
- Display / DisplayFor / DisplayForModel methods all into `HtmlHelperDisplayExtensions`
- Partial / RenderPartial methods all into `HtmlHelperPartialExtensions`
- use `IHtmlHelper<TModel>` everywhere
- correct `ArgumentNullOrEmpty` and pass parameter name to
`ArgumentException` constructor
- remove `[SuppressMessage]` attributes
- `AnonymousObjectToHtmlAttributes` should return an `IDictionary`
- `var`
- remove straggling copyright notices
- wrap long lines (did not reword any comments)
- align a few parameters
- add missing `[NotNull]` attributes
- remove now-unneeded usings for ...ModelBinding.Internal namespace
Also get ModelBinding test project working under CoreCLR
- create separate k10 and net45 folders under test in VS
- add `[InternalsVisibleTo]` to make `TypeExtensions` visible to test assembly
- correct tests' `CultureInfo` use to compile under CoreCLR
- ifdef out CoreCLR tests depending on Moq, ReadOnly, ...
- remove a couple of tests expecting TypeConverter to work