Add device management docs to docs.json

Add device management files to evaluation to production section as a test.

Author: Amanda Butler

docs.json

@@ -1018,6 +1018,15 @@
                 "sources": [{
                         "url": "https://github.com/ARMmbed/evaluation-to-production/blob/5.11/FE2P/stage_2/1_hardware.md"
                     },
+                    {
+                        "url": "https://github.com/ARMmbed/mbed-os-5-docs/blob/development/docs/device-management.md"
+                    },
+                    {
+                        "url": "https://github.com/ARMmbed/mbed-os-5-docs/blob/development/docs/device-management-config.md"
+                    },
+                    {
+                        "url": "https://github.com/ARMmbed/mbed-os-5-docs/blob/development/docs/device-management-test.md"
+                    },
                     {
                         "url": "https://github.com/ARMmbed/evaluation-to-production/blob/5.11/FE2P/stage_2/3_connectivity.md"
                     },