Sales order support (#438)

* Add new models for SalesOrder

- Create generic Order and OrderLine models with common functionality

* Refactor

- Move some widgets around
- Cleanup directory structure

* Add link to home screen and nav drawer

* Add SalesOrder list widget

* Linting fixes

* Fix string

* Refactor PurchaseOrderDetailWidget

* Tweaks to existing code

* linting

* Fixes for drawer widget

* Add "detail" page for SalesOrder

* Add more tiles to SalesOrder detail

* Allow editing of salesorder

* add list filters for sales orders

* Display list of line items

* Customer updates

- Display customer icon on home screen
- Fetch sales orders for customer detail page

* Cleanup company detail view

* Create new sales order from list

* Stricter typing for formFields method

* Create new PurchaseOrder and SalesOrder from company deatil

* Status code updates

- Add function for name comparison
- Remove hard-coded values

* Update view permission checks for home widget

* Add ability to manually add SalesOrderLineItem

* Add nice progress bar widgets

* Display detail view for sales order line item

* edit SalesOrderLineItem

* Fix unused import

* Hide "shipped items" tab

- Will be added in a future update

lib/generated/i18n.dart

@@ -1,8 +1,8 @@
 
-import 'dart:async';
+import "dart:async';
 
-import 'package:flutter/foundation.dart';
-import 'package:flutter/material.dart';
+import "package:flutter/foundation.dart';
+import "package:flutter/material.dart';
 // ignore_for_file: non_constant_identifier_names
 // ignore_for_file: camel_case_types
 // ignore_for_file: prefer_single_quotes