added AESGCM and protable bouncy castle package

updated IUserRepository and IUserService

Added IUserService and UserService and configured dependency injection in startup.cs

updated user repository methods, added create and update user view models

Added constructor for UserRepository

Created IUserRepository and User Repository and configured dependency injection in start.cs

Updated user table validation and initial migration

Added initial migration

Added User And Refresh Token Models

Injected Dependency for AddDbContext in startup, Added Microsoft.EntityFrameworkCore.SqlServer

Added Microsoft.EntityFramework.Tools

Added EntityFrameWorkCore and Created AppDbContext

Setup Web Api project and configured swagger