Remove compiler directives and asp.net core code

[kevinkuszyk]

We've now moved the mvc core code out into another repro, but we still have the compiler directives and mvc code usings here. These can all be removed now.

[rikrak]

I've added a PR for this. Is it possible to link PRs with issues?

[rikrak]

Experimental link: #39

[kevinkuszyk]

Thanks for the PR - it's much appreciated!