Use CallerArgumentExpressionAttribute in throw helpers

[IliaBrahinets]

The following changes have been made in throw helpers:

• Added CallerArgumentExpressionAttribute to simplify throw assertions (nameof(parameterName) can be omitted in most cases)
• Added StringSyntaxAttribute for error message templates

[CLAassistant]

All committers have signed the CLA.

[dlemstra]

Thanks for your pull request it will probably take a while before I have time to look at this. Only quick thing that I saw was string? message = "Must not be null". I don't want to change the default message for a ArgumentNullException so please restore those two overloads.

[IliaBrahinets]

Removed the default value for IfNull message. The are multiple options with overloads:

1. IfNull([NotNull] object? value, [CallerArgumentExpression(nameof(value))] string? paramName = null, string? message = null)
2. IfNull([NotNull] object? value, [CallerArgumentExpression(nameof(value))] string? paramName = null) and IfNull([NotNull] object? value, string message, [CallerArgumentExpression(nameof(value))] string? paramName = null)
3. IfNull([NotNull] object? value, [CallerArgumentExpression(nameof(value))] string? paramName = null) and IfNull([NotNull] object? value, [CallerArgumentExpression(nameof(value))] string? paramName = null, string? message = null)

The third option causes ambiguity for Throw.IfNull(value) call, while the second isn't cosistent in terms of paramName positioning. I decided to implement the first approach for all throw helpers except overloads with message arguments. Awaiting for your feedback on this.

[dlemstra]

It looks like you did not address that issue yet? Doing new ArgumentNullException(paramName, null) is not the same as new ArgumentNullException(paramName).