coroutine dispatcher for network code example

Example: coroutine dispatcher for network

+-----------------------------------+|         Dispatchers.Main          |+-----------------------------------+| Main thread on Android, interact  || with the UI and perform light     || work                              |+-----------------------------------+| - Calling suspend functions       || - Call UI functions               || - Updating LiveData               |+-----------------------------------++-----------------------------------+|          Dispatchers.IO           |+-----------------------------------+| Optimized for disk and network IO || off the main thread               |+-----------------------------------+| - Database*                       || - Reading/writing files           || - Networking**                    |+-----------------------------------++-----------------------------------+|        Dispatchers.Default        |+-----------------------------------+| Optimized for CPU intensive work  || off the main thread               |+-----------------------------------+| - Sorting a list                  || - Parsing JSON                    || - DiffUtils                       |+-----------------------------------+