Add Create method for types MONITORINFO and MONITORINFOEX

[psulek]

Is your feature request related to a problem? Please describe.
Type MONITORINFO and MONITORINFOEX both have field cbSize, which as described in docs must be set via sizeof() before calling method GetMonitorInfo() (both overloads).

This can be confusing for new users (especially new C#/dotnet coders) that calling var info = new MONITORINFO(); is not enough, and required construct is: var info = new MONITORINFO{ cbSize = sizeof(MONITORINFO) };

Also there can be (depends on user code context) error like: 'MONITORINFO' does not have a predefined size, therefore sizeof can only be used in an unsafe context.

Describe the additions or enhancements you'd like
Create static method Create() for both types MONITORINFO and MONITORINFOEX which will set cbSize automatically for user.

[dahall]

Thank you for submitting a PR. In many places in the project I have used the public static STRUCTNAME Default => new() { cbSize = (uint)Marshal.SizeOf(typeof(STRUCTNAME)) } pattern, rather than the Create method pattern. See here. For consistency, will you adapt your PR to use the library pattern and then I'll accept?

[psulek]

Sure, sounds good!