Fixed the default header css style

Fixed span styling when we specify a tooltip to use header class
Added border color for highlight selection via props
Added material ui/icons as devDependency for storybook and as peer for production
Added a validation for given width % and throws error if overflows the limit
Removed theme from props and added inside apiRef
Added a new rowsApi method "getRowAt" in order to allow index based search
Refactored the existing getRows with array index and replaced with getRowAt
Removed rows as editorManager dependecy
Added additionalProps on editors that receive dynamically editorProps from column and editorClass from theme
Removed the calendar default styles and moved as external configuration for Spreadsheet
Fixed the rows not updating in the grid due to createData not using the latest rows and always going on the API
Fixed the spreadsheet storybook example where the state was staling

package.json

@@ -32,11 +32,11 @@
   },
   "peerDependencies": {
     "react": ">= 16.13.1",
-    "react-dom": ">= 16.13.1"
+    "react-dom": ">= 16.13.1",
+    "@material-ui/core": "^4.11.0",
+    "@material-ui/icons": "^4.9.1"
   },
   "dependencies": {
-    "@material-ui/core": "^4.11.0",
-    "@material-ui/icons": "^4.9.1",
     "@xobotyi/scrollbar-width": "^1.9.5",
     "babel-loader": "^8.1.0",
     "babel-preset-react-app": "^9.1.2",
@@ -49,6 +49,8 @@
     "resize-detector": "^0.2.2"
   },
   "devDependencies": {
+    "@material-ui/core": "^4.11.0",
+    "@material-ui/icons": "^4.9.1",
     "@babel/preset-typescript": "^7.10.4",
     "@storybook/addon-options": "~5.1.11",
     "@storybook/addon-storysource": "~5.1.11",