Fixed ThemeStorage inheritance

refs https://github.com/TryGhost/Toolbox/issues/95

- The ThemeStorage was never supposed to inherit image specific mehods. The LocalStorageBase is all it needs, might be even too much
- Look mum no saveRaw!

core/server/adapters/storage/LocalStorageBase.js

@@ -24,7 +24,7 @@ class LocalStorageBase extends StorageBase {
      *
      * @param {Object} options
      * @param {String} options.storagePath
-     * @param {String} options.staticFileURLPrefix
+     * @param {String} [options.staticFileURLPrefix]
      * @param {Object} [options.errorMessages]
      * @param {String} [options.errorMessages.notFound]
      * @param {String} [options.errorMessages.notFoundWithRef]
@@ -102,7 +102,7 @@ class LocalStorageBase extends StorageBase {
                     maxAge: constants.ONE_YEAR_MS,
                     fallthrough: false,
                     onEnd: () => {
-                        logging.info('LocalFileStorage.serve', req.path, moment().diff(startedAtMoment, 'ms') + 'ms');
+                        logging.info('LocalStorageBase.serve', req.path, moment().diff(startedAtMoment, 'ms') + 'ms');
                     }
                 }
             )(req, res, (err) => {

core/server/services/themes/ThemeStorage.js

@@ -4,16 +4,16 @@ const path = require('path');
 const config = require('../../../shared/config');
 const security = require('@tryghost/security');
 const {compress} = require('@tryghost/zip');
-const LocalFileStorage = require('../../adapters/storage/LocalFileStorage');
+const LocalStorageBase = require('../../adapters/storage/LocalStorageBase');
 
 /**
  * @TODO: combine with loader.js?
  */
-class ThemeStorage extends LocalFileStorage {
+class ThemeStorage extends LocalStorageBase {
     constructor() {
-        super();
-
-        this.storagePath = config.getContentPath('themes');
+        super({
+            storagePath: config.getContentPath('themes')
+        });
     }
 
     getTargetDir() {

core/shared/config/defaults.json

@@ -23,7 +23,7 @@
         }
     },
     "storage": {
-        "active": "LocalFileStorage",
+        "active": "LocalImagesStorage",
         "media": "LocalMediaStorage",
         "LocalMediaStorage": {}
     },