v5.0.0

The 5.0.0 release of GoldSim focuses on major upgrades to backend dependencies which introduced a number of breaking changes. Notably, this includes upgrading to .NET 5.0 and ASP.NET Core 5.0, as well as OnTopic 5.0.0 and OnTopic Editor 5.0.0. The updates to OnTopic, in particular, introduced a significant number of breaking changes which required updating quite a few API calls to maintain the existing functionality. This release does not include any significant design changes or new features.