refactor(conf): cleanup unused config file (issue #536)

src/config/config.json

-{
-  "matomoTrackerUrl": "",
-  "matomoSiteId": "",
-  "ghostAdmin": "http://localhost:2368/ghost/"
-}

src/config/config.template.json

-{
-  "matomoTrackerUrl": "https://statweb.grandlyon.com/",
-  "matomoSiteId": "87",
-  "ghostAdmin": "http://localhost:2368/ghost/"
-}