reduced & modified version of the original BlackLib
Reduced and modified version v3_0 of https://github.com/yigityuce/BlackLib.git to allow subclassing of BlackGPIO. Removed all other features of BlackLib.
The original verision of BlackLib can be used with projects found in my github provided the topmost BlackLib classes have the keyword "virtual" removed from the base class in the class declaration.
ie:
original
class BlackCoreGPIO : virtual private BlackCore
{...
required changes
class BlackCoreGPIO : private BlackCore
{...