What's new in 4.0.0
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— Breaking changes:
* AdjustTimeout behaves as user would expect.
* Original AdjustTimeout renamed to AdjustAndLimitTimeout
* Added nullability annotations to serveral methods in old .NET versions even if they don't match the base interfaces
* Nullability improvements
* Added Code.NotNullNorEmptyAndItemNotNull
* Add C# nullability markup.
* Remove JetBrains nullability markup: NotNull/CanBeNull/ItemNotNull.
* Remove deprecated targets. Supporting: .NET 3.5+, .NET Standard 2.0+, .NET Core 3.1+.
* Fixed Range string representation bug.
* Refactoring & code cleanup