#24 updated docs for mutliple spreadsheets data preview release

+ updated demo global sales by category test data config file

README.md

@@ -12,9 +12,10 @@ large `.csv/.tsv`, `.xlsx/.xlsm`, `.json` array, `.arrow`, `.avro` & `.parquet`
 - Basic Data Charts creation with Aggregate Functions, Row & Column Pivots
 - Pluggable Data Charting libraries for stock Charts: [highcharts](https://www.highcharts.com/demo) || [d3fc](https://d3fc.io/)
 - Persistent Data Preview Settings (Sort, Filter, Pivots, etc.) for restore of open panels on vscode Reload
+- Mulptiple Spreadsheets Data Preview for `Excel` data files
 - Arrow & Avro `.schema.json` generation & binary `Excel` data files `.json` data generation for text data preview
 - Filtered data `.json` & `.csv` Save file options
-- Save and Load data view config options
+- Save and Load data view `.config` options
 - Dark & Light Data Preview Panel Themes
 
 ![Perspective Viewer](https://github.com/RandomFractals/vscode-data-preview/blob/master/images/perspective-viewer.gif?raw=true 

data/Demographics-GlobalSales-by-category.config

@@ -1,11 +1,10 @@
 {
   "config": {
     "aggregates": "{\"Address\":\"count\",\"Category\":\"count\",\"City\":\"count\",\"Country\":\"count\",\"Distributor\":\"count\",\"Item Type\":\"count\",\"Path\":\"count\",\"Product\":\"count\",\"Sales Person\":\"count\",\"State\":\"count\",\"Order Date\":\"count\",\"Total Amount\":\"sum\",\"Postal Code\":\"sum\"}",
-    "class": "dragging",
     "column-pivots": "[]",
-    "columns": "[\"Address\",\"City\",\"Country\",\"Distributor\",\"Item Type\",\"Order Date\",\"Path\",\"Postal Code\",\"Product\",\"Sales Person\",\"Total Amount\",\"State\"]",
+    "columns": "[\"Birth Date\",\"Date First Purchase\",\"Education\",\"Gender\",\"Home Owner Flag\",\"Marital Status\",\"Number Cars Owned\",\"Number Children At Home\",\"Occupation\",\"Total Children\",\"Total Purchase YTD\",\"Yearly Income\"]",
     "filters": "[]",
-    "row-pivots": "[\"Category\"]",
+    "row-pivots": "[]",
     "settings": "true",
     "sort": "[[\"Category\",\"asc\"]]",
     "view": "grid"