Fix for #996 - ViewComponentInvoker should get TypeActivator from DI.
Rename GlobalModel -> ApplicationModel

This also comes with a rename of the namespace
Microsoft.AspNet.Mvc.ApplicationModel to
Microsoft.AspNet.Mvc.ApplicationModels.

Also tuned up some parameter and variable names for increased
understandability.
Reacting to System.Collections.Concurrent versioning change
Changing NewtonSoft.Json version to 6.0.6
Change TagBuilder Attributes and HTML Helper dependencies to be case insensitive.

- This involved adding the StringComparer.OrdinalIgnoreCase comparer to the TagBuilder's Attributes dictionary.
- Added tests to validate that all methods that made use of TagBuilder.Attributes abide by the new ignore case mechanic.
- Added two sets of tests to validate the new functionality of Object => Dictionary HTML helper tests.
- Modified a functional test that utilizes HTML Helpers to provide same attribute-different case objects.
- Fixed existing HTML helper tests to account for new ordering of attrbutes (dictionary no longer adds key value pairs, it sets them).

#1328
React to case insensitive TagHelperOutput.Attributes.

- Cleaned up some existing bad code that worked around case sensitive TagHelperOutput.Attributes.
- Modified MergeAttributes to be case insensitive when it comes to merging class attributes.
- Added a test to verify the new MergeAttribute case insensitive class merging.

aspnet/Razor#186
Modifying ArgumentNullOrEmpty message to be consistent with Mvc 5 \
testing code.
Don't lock metadata references
Change `ViewDataDictionary` copy constructor to ensure `ModelMetadata` is
 never that for `object`
- `ViewDataDictionary<TModel>.ModelMetadata` was for `object` after base
 copy constructor got value from `ViewDataDictionary<object>`
- problem led to #1426 symptoms
- with copy constructor leaving `base.ModelMetadata==null` more often,
 `ViewDataDictionary<TModel>.ModelMetadata` usually tracks `TModel` if
 `Model==null`

nit:
- fix existing comment in main `ViewDataDictionary` copy constructor
Add "/home/nulluser" view to MVC sample
- exercises display and editor helpers when `Model==null`
Add more unit tests of `ViewDataDictionary` copy constructors
Merge branch 'release' into dev
* Porting Hidden and HiddenFor unit tests

Partial fix to #453
Reacting to Roslyn version changes
Merge branch 'release' into dev
Change logging in Mvc to log with TraceType.Verbose
Fixes #1457
Merge branch 'release' into dev
Fix for #1448 - ViewComponents must be public top-level classes

ViewComponents and Controllers now follow the same rules exactly for what
types of classes they can be.

Also corrected a bug in a test for controllers. Closed-generic types can
be controllers, the test was wrong.
TODO removal part 1 - ActionExecutorTests
Fix for #1442 - Find better names for ApiExplorerProperties

Taking the suggestion here to move these to a sub-object. This is future
proof in the event that we need to capture more data for ApiExplorer, and
reads better.