This change adds an API for Tag Helper discovery.
I also got rid of the 'design time' flag for the provider as an
experimental change. We need to think through the consequences of this
before committing to it. Right now I've left those tests failing until we
can make a decision.
This change decouples VCTH discovery a bit more, but we're still not ready
to move that into a the MVC extensions assembly. For that we need the
ability to discover the MVC extensibility.
N. Taylor Mullen
Ajay Bhargav Baaskaran
Ryan Brandenburg
Ryan Nowak