Introduced ICommandHandler
Removed Unity
Introduced Ninject
Introduced CommandDispatcher
Reworked Queries and Commands
Fixed default Ninject binding (it now supports internal classes)
Fixed ICommandHander and IQueryHandler bindings
Commented unclear part of AvaabilityDurationCalculator
Added AddProductCommandHandler and covered it with tests
Implemented TakeProductCommandHandler and covered it with tests
Removed ProductsControllerTests as all tests from it were moved to commands tests
Implemented AddSupplyCommandHandler and covered it with tests
Added a test for AddSupplyCommandHandler