The Equals method was using reference equality to compare ITypeReference instances.  Correct comparison of that type must use .Equals as equivalent generic values can be different objects.

This surfaced as a bug in determinism.  In the case we had an alias'd using where the target type was generic this Equals method came into play.  Based on whether we got a generic cache hit or not ended up changing the PDB output and as an effect the determinism id of the resulting assembly.

closes #7015

With Visual Studio 2015 Update 1 you should not specify -anycpu
in the runtimes section. Right now we'll have both to allow us to build
with and without Update 1, and we'll remove the old ones once we've
made the transition.

Update 1 also tries deploying implementations for some class libraries,
so I'm updating all our test and VSIX deployment class libraries to
now include implementations.

Updating System.Reflection.Metadata to 1.1.0-alpha-0015 and System.Collections.Immutable to 1.1.37.0

Revert "Updating System.Reflection.Metadata to 1.1.0-alpha-0015 and System.Collections.Immutable to 1.1.37.0"

This reverts commit d78dbb97.

Updating System.Reflection.Metadata to 1.1.0-alpha-0015 and System.Collections.Immutable to 1.1.37.0

Reverting System.Collections.Immutable back to 1.1.36 until we can upgrade System.Reflection.Metadata simultaneously

Updating Microsoft.DiaSymReader to v1.0.6, Microsoft.DiaSymReader.Native to v1.2.0, and System.Collections.Immutable to v1.1.37