(core) i18

Summary:
Adding initial work for localization support.

Summary in https://grist.quip.com/OtZKA6RHdQ6T/Internationalization-and-Localization

Test Plan: Not yet

Reviewers: paulfitz

Reviewed By: paulfitz

Subscribers: paulfitz

Differential Revision: https://phab.getgrist.com/D3633

app/client/ui/AddNewButton.ts

@@ -1,13 +1,14 @@
 import {theme, vars} from 'app/client/ui2018/cssVars';
 import {icon} from 'app/client/ui2018/icons';
 import {dom, DomElementArg, Observable, styled} from "grainjs";
+import {t} from 'app/client/lib/localization';
 
 export function addNewButton(isOpen: Observable<boolean> | boolean = true, ...args: DomElementArg[]) {
   return cssAddNewButton(
     cssAddNewButton.cls('-open', isOpen),
     // Setting spacing as flex items allows them to shrink faster when there isn't enough space.
     cssLeftMargin(),
-    cssAddText('Add New'),
+    cssAddText(t('AddNew')),
     dom('div', {style: 'flex: 1 1 16px'}),
     cssPlusButton(cssPlusIcon('Plus')),
     dom('div', {style: 'flex: 0 1 16px'}),