Execute `dnu restore` with .NET Core and use Mono 4.0.5 - upgrade Linux to Trusty (Ubuntu 14.04) distribution, where .NET Core is supported   - also start testing with .NET Core xplat - Mono beta is now 4.2.1 which doesn't work with `nuget.exe`   - see also aspnet/External#48
Execute `dnu restore` with .NET Core and use Mono 4.0.5
- upgrade Linux to Trusty (Ubuntu 14.04) distribution, where .NET Core is supported
  - also start testing with .NET Core xplat
- Mono beta is now 4.2.1 which doesn't work with `nuget.exe`
  - see also aspnet/External#48

aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore