BIG-4: fix splash screen page should be not scrollable and should appear before execute javascript.

client/src/containers/Sales/Invoices/InvoicesLanding/components.js

@@ -6,9 +6,6 @@ import {
   MenuItem,
   MenuDivider,
   ProgressBar,
-  Popover,
-  Position,
-  Button,
 } from '@blueprintjs/core';
 import intl from 'react-intl-universal';
 import moment from 'moment';

client/src/style/components/BigcapitalLoading.scss

@@ -1,7 +1,7 @@
 .bigcapital-loading {
   height: 100%;
   width: 100%;
-  position: absolute;
+  position: fixed;
   display: flex;
   background: #fff;
   z-index: 999999;