Package reference fixes (#965) * Use PackageReference for referencing packages, References for referencing assemblies * Fixed test passing for the wrong reason * Rename Compiler.PackageReference to PackageReferences * Don't fast hotload if a referenced assembly has changed * More assembly / package reference strictness * Made generic method resolving / comparing stricter * We need to re-resolve all member references in fast-hotloaded methods * More precise logic when deciding if a referencing assembly can be fast-hotloaded * Constructor resolution regression fix * Some cleanup in ILGeneratorExtensions * Hotload.GetMethods helper now matches name * Access control now caches assembly definitions by name + version * Assert that the correct assembly definition version is resolved * Keep exactly the outgoing assembly definition cached, but dispose older versions * Clean up AccessControl.Resolve a bit * WIP referencing fast-hotloaded assembly fix * Fixed unloading IsolatedAssemblyContexts during fast hotload * Remove some logging * Fix menu breaking after hotload * WIP force-reload assemblies that depend on a changed package * Allow resolving newer assembly versions * PackageLoader.LoadAssemblyFromPackage cleanup * Only force an assembly reload if dependent package did a full hotload * Fix exception in ContextTools.DetermineContext in fast hotloaded methods * Init TypeLibrary in TestUI.Panels.PanelTests * Description codegen: just allow multiple [Description] instead of being non-deterministic