.NET 8.0 support

Changes

• Add support for .NET Core 8.0;
• Remove .NET Core 2.2 support;
• Update Newtonsoft JSON to version 13.0.3;

'Nova Poshta' client 1.4.0

Changes:

• Added internet document 'update' method to DocumentService;
• Added internet document 'delete' method to DocumentService;
• Updated create document method according to latest API documentation;
• Updated Newtonsoft.Json library to version 13.0.2;

Version 1.2.2

It's latest library version, which supports all methods of 'Nova Poshta' REST API.
Supported versions .NET Core:

• .NET Core 2.2;
• .NET Core 3.1;
• .NET Core 5.0;

Unfortunately I haven't so mu time to test all methods, so I will be very thankful if you write me here about library issues.

Version 1.0.7

It's first Nova Poshta client release.
Library contains fully implemented model methods:

• Address
• Common
• Document(partial)