223883 Correct SimpleBackgroundTransfer sample to export optional protocol s…

[SoupChef] Fix build with Xcode 12.2 (#409) Xcode 12.2 - adds `arm64` to the simulator architectures - removes `i386` from the simulator architectures `lipo` cannot create a _classic_ fat archive with `arm64` simulator and `arm64` device slices - since they are the same architecture. This requires `.xcframework` support which is not yet supported by XI and XM. However we can tweak the build to do: - x86_64 only for simulator, which is the only support arch for XI today - arm64 for devices and that makes `lipo` happy and we can continue to have this sample under test automation. Note: the original `.a` names were incorrect as they did not match the architectures that were present in the files. I changed them to mention the platform.

[UICatalog] Fix ambiguous call in sample (#408) a new API with a similar signature (wrt null) was added in XI 14

Remove invalid project from FileSystemSampleCode (#404) The FileSystem2.csproj project does not exist, its entry has been removed from WorkingWithTheFileSystem.sln.

Fix ColorFeed sample by adding required Info.plist keys (#393) - https://github.com/xamarin/ios-samples/issues/392

111390 fix spelling mistake

111387 [background] update project

103176 [MemoryDemo] Make sure the same output path isn't used with multiple …

95115 Update README.md

94197 Update README.md