Merge branch 'multi-tenancy' into 'master'

Tsi1.Api/Tsi1.BusinessLayer/Services/ForumService.cs

Tsi1.Api/Tsi1.BusinessLayer/Services/MessageService.cs

Tsi1.Api/Tsi1.BusinessLayer/Services/PostMessageService.cs

Tsi1.Api/Tsi1.BusinessLayer/Services/UserService.cs

Tsi1.Api/Tsi1.DataLayer/Entities/Course.cs

Tsi1.Api/Tsi1.DataLayer/Entities/Message.cs

Tsi1.Api/Tsi1.DataLayer/Entities/PostMessage.cs

Tsi1.Api/Tsi1.DataLayer/Entities/Professor.cs

Tsi1.Api/Tsi1.DataLayer/Entities/Student.cs

Tsi1.Api/Tsi1.DataLayer/Entities/Tenant.cs

Tsi1.Api/Tsi1.DataLayer/Entities/User.cs

...Tsi1.DataLayer/EntityConfiguration/CourseConfiguration.cs

.../Tsi1.DataLayer/EntityConfiguration/ForumConfiguration.cs

...i/Tsi1.DataLayer/EntityConfiguration/PostConfiguration.cs

...1.DataLayer/EntityConfiguration/ProfessorConfiguration.cs

...si1.DataLayer/EntityConfiguration/StudentConfiguration.cs

...Tsi1.DataLayer/EntityConfiguration/TenantConfiguration.cs

...i/Tsi1.DataLayer/EntityConfiguration/UserConfiguration.cs

...r/Migrations/20201022010216_add-multy-tenancy.Designer.cs

....DataLayer/Migrations/20201022010216_add-multy-tenancy.cs