All enum values not handled in switch cases. ( -Wswitch-enum ) #889

Bug Report

• What is the issue you have?
  I am having issues while compiling a C++ program using the json.hpp file. I am using the complier options -Wswitch-enum and -Werror. I see that all the enums are not handled in the switch cases, which is why I am seeing some errors while compiling.

• Please describe the steps to reproduce the issue. Can you provide a small but working code example?
  Include the json.hpp in the header of a c++ program and compile the program using -Wswitch-enum and -Werror options.

• What is the expected behavior?
  All enums must be handled and there should be no errors while using these compiler options.

• And what is the actual behavior instead?
  Actual behaviour: It throws the errors like "src/json.hpp:3005:9: error: enumeration value ‘end_array’ not handled in switch [-Werror=switch-enum]"

• Which compiler and operating system are you using? Is it a supported compiler?
  Im using a Ubuntu OS and using a supported compiler.

• Did you use a released version of the library or the version from the develop branch?
  Used from 'develop' branch.

• If you experience a compilation error: can you compile and run the unit tests?
  Not experiencing any issues with the existing compiler options. Errors only when using -Wswitch-enum and -Werror.

Feature Request

• Describe the feature in as much detail as possible.

• Include sample usage where appropriate.