Added PluginClassImplementation which is to be able to implement interfaces of another module where the interface is not directly accessible (e.g.: is a friend API).
Added PluginClassConstructor.
Added some utility methods to ReflectionHelper.
Refactored PluginClassConstructor.
Refactored PluginClassConstructorTest.
Added null check to PluginClassConstructor.
Added PluginClassMethod.