move themes and plugins into config file

src/scripts/themeManager.js

@@ -0,0 +1,66 @@
+import * as webSettings from 'webSettings';
+
+var themeStyleElement;
+var currentThemeId;
+
+function unloadTheme() {
+    var elem = themeStyleElement;
+    if (elem) {
+        elem.parentNode.removeChild(elem);
+        themeStyleElement = null;
+        currentThemeId = null;
+    }
+}
+
+function getThemes() {
+    return webSettings.getThemes();
+}
+
+function getThemeStylesheetInfo(id) {
+    return getThemes().then(themes => {
+        var theme = themes.find(theme => {
+            return id ? theme.id === id : theme.default;
+        });
+
+        return {
+            stylesheetPath: 'themes/' + theme.id + '/theme.css',
+            themeId: theme.id
+        };
+    });
+}
+
+function setTheme(id) {
+    return new Promise(function (resolve, reject) {
+        if (currentThemeId && currentThemeId === id) {
+            resolve();
+            return;
+        }
+
+        getThemeStylesheetInfo(id).then(function (info) {
+            if (currentThemeId && currentThemeId === info.themeId) {
+                resolve();
+                return;
+            }
+
+            var linkUrl = info.stylesheetPath;
+            unloadTheme();
+
+            var link = document.createElement('link');
+            link.setAttribute('rel', 'stylesheet');
+            link.setAttribute('type', 'text/css');
+            link.onload = function () {
+                resolve();
+            };
+
+            link.setAttribute('href', linkUrl);
+            document.head.appendChild(link);
+            themeStyleElement = link;
+            currentThemeId = info.themeId;
+        });
+    });
+}
+
+export default {
+    getThemes: getThemes,
+    setTheme: setTheme
+};