Completed realimage Challenge 2016

[vipultripathi04]

• Add DistributorService to validate distributor permissions across included and excluded regions
• Implement DistributorHandler to process HTTP requests for permission checks
• Create CitiesRepository to read and manage geographic locations from CSV
• Add Location and DistributorRequest models for API contracts
• Implement permission validation logic with region matching capabilities
• Add formatLocation helper to standardize location string formatting
• Configure Gorilla Mux router for RESTful API endpoints
• Set up application configuration with configurable port settings