@ohif/i18n: Fix issues with exports and update docs (#598)

* update i18n version -- already published

* update ohif/i18n version and add modules

* update ohif/i18n version

* update translating documentation

* replace addLocales method and exported modules

* lock files

* Update index.js

* fix(@ohif/i18n): export custom methods in the main i18n object

`initI18n`, `addLocales` and `T` are now being exported inside the main `i18n` object.

* remove unecessary dependencies

* update vtk-extension lock file

extensions/ohif-i18n/src/index.js

@@ -6,8 +6,6 @@ import pkg from '../package.json';
 import { debugMode, detectionOptions } from './config';
 import locales from './locales';
 
-let translate;
-
 function addLocales(newLocales) {
   customDebug(`Adding locales ${newLocales}`, 'info');
 
@@ -44,8 +42,8 @@ function initI18n(detection = detectionOptions) {
       },
     })
     .then(function(t) {
-      translate = t;
-      customDebug(`t function available.`, 'info');
+      i18n.T = t;
+      customDebug(`T function available.`, 'info');
     });
 }
 
@@ -53,6 +51,7 @@ customDebug(`version ${pkg.version} loaded.`, 'info');
 
 initI18n();
 
-export { translate as t, addLocales, initI18n };
+i18n.initI18n = initI18n;
+i18n.addLocales = addLocales;
 
 export default i18n;