Allows loading cli adapters from module path

src/cli/cli-definitions.js

@@ -53,6 +53,9 @@ export default {
     env: "PARSE_SERVER_PUSH",
     help: "Configuration for push, as stringified JSON. See https://github.com/ParsePlatform/parse-server/wiki/Push",
     action: function(opt) {
+      if (typeof opt == 'object') {
+        return opt;
+      }
       return JSON.parse(opt)
     }
   },
@@ -60,6 +63,9 @@ export default {
     env: "PARSE_SERVER_OAUTH_PROVIDERS",
     help: "Configuration for your oAuth providers, as stringified JSON. See https://github.com/ParsePlatform/parse-server/wiki/Parse-Server-Guide#oauth",
     action: function(opt) {
+      if (typeof opt == 'object') {
+        return opt;
+      }
       return JSON.parse(opt)
     }
   },
@@ -100,17 +106,44 @@ export default {
     help: "Mount path for the server, defaults to /parse",
     default: "/parse"
   },
-  "databaseAdapter": {
-    env: "PARSE_SERVER_DATABASE_ADAPTER",
-    help: "Adapter module for the database sub-system"
-  },
   "filesAdapter": {
     env: "PARSE_SERVER_FILES_ADAPTER",
-    help: "Adapter module for the files sub-system"
+    help: "Adapter module for the files sub-system",
+    action: function action(opt) {
+      if (typeof opt == 'object')  {
+        return opt;
+      }
+      try {
+        return JSON.parse(opt);
+      } catch(e) {}
+      return opt;
+    }
+  },
+  "emailAdapter": {
+    env: "PARSE_SERVER_EMAIL_ADAPTER",
+    help: "Adapter module for the email sending",
+    action: function action(opt) {
+      if (typeof opt == 'object')  {
+        return opt;
+      }
+      try {
+        return JSON.parse(opt);
+      } catch(e) {}
+      return opt;
+    }
   },
   "loggerAdapter": {
     env: "PARSE_SERVER_LOGGER_ADAPTER",
-    help: "Adapter module for the logging sub-system"
+    help: "Adapter module for the logging sub-system",
+    action: function action(opt) {
+      if (typeof opt == 'object')  {
+        return opt;
+      }
+      try {
+        return JSON.parse(opt);
+      } catch(e) {}
+      return opt;
+    }
   },
   "maxUploadSize": {
     env: "PARSE_SERVER_MAX_UPLOAD_SIZE",