Improve handling with an IoC container

Hi there
Thank you for the SendGrid C# library. I want to use this library with an IoC Container (e.g. Ninject, Funq or Unity). I assume that the GetInstance Factory Method could be a problem for the usage with a specific IoC-Container.

My suggestion:
- Removing all GetInstance Methods (It's a factory method which only call the specific constructor with default parameters - you can do the same with overload constructors)
- Make the constructors of the SendGrid / Web class public

What do you think about my suggestion?

Thanks for your response.

Kind regards, patrick