The new @namespace directive isn't sanitizing class and namespace names
when generating them. This means that a file-system-legal character like
'-' will show up in a class name, and that's not good.
Note that the old code paths (document classifiers) already had tests for
this and did it properly. It was only missing from @namespace.
This change removes the default usings for 'System' and
'System.Threading.Tasks' and adds them to the MVC template engine.
This is preparation for removing this feature from the razor options, I
wanted to get all of the intentional diff out of the way.
Ryan Nowak
N. Taylor Mullen
Jass Bagga
Ryan Brandenburg