#31 Created classes for API prototype
#31 Created events API; model interfaces moved to new project
#31 Fixed namespaces of model interfaces and enums
API prototype thoughts implementation.
#31 removed Api and Api.Interfaces modules, other API modifications
#31 API solution: core modifications
#31 API solution modifications
#31 API: created events container
#31 Merge branch 'dev' into dev-api

Conflicts:
	BetterCms.Core/BetterCms.Core.csproj
	BetterCms.Core/DataContracts/IPage.cs
	Modules/BetterCms.Module.Pages/Controllers/ContentController.cs
#31 API: created API services without implementation; author service implementation; tests for implemented services; media entities and interfaces;
#31 APIE created redirects, layouts, categories API services implementations and tests
#31 API: created queryable API service methods for tests
#31 API: reverted last changes (removed most of interfaces);
#31 API: refactored API, created contexts for each module, refactored service implementations, created new tests, etc.
#31 API tests modifications
#31 API: created solution for events
#31 API: implemented new service methods, media mocked tests converted to database integration tests
#31 API: implemented contents API service
#31 API: Created CmsApiException and added exception handling in API Services
#31 Merged changed from dev -> dev-api
Merge branch 'dev' into dev-api

Conflicts:
	Modules/BetterCms.Module.Pages/Command/Widget/SaveWidget/SaveServerControlWidgetCommand.cs
	Modules/BetterCms.Module.Root/Services/DefaultContentService.cs