Master services failing to start due to issue in config

Issue

• After making a few small changes to the master config, the service fails to start with the following error:
  ~~~
  json: expect char '"' but got char '{'
  ~~~
• Seeing the following error after modifying the master config file:

    <DATETIME>       1 start_api.go:68] could not load config file "/etc/origin/master/master-config.yaml" due to an error: error reading config: [pos 6545]: json: expect char '"' but got char '{'