Updated for 1.0.0-alpha4

Updated to work with 1.0.0-alpha4

Things to notice:
* I locked the version to 1.0.0-alpha4 in project.json. I think this needs to be manually updated when beta ships, * versions don't make sense here.
* I added wwwroot with a blank .gitignore so the empty directory can be added to git
* I don't believe it's possible to get it working on both Mac and Windows in alpha4 - Windows packages have dependencies that aren't working on Mac.
* Added master .gitignore to exclude packages, etc.
* I removed the Welcome page since I don't think it makes sense in an MVC application with a default route