Added first codemod (for renamed components)

CHANGELOG.md

@@ -7,7 +7,7 @@ Upgrade instructions and [jscodeshift](https://github.com/facebook/jscodeshift)
 
 To run a code mod, check out react-virtualized (or download the codemod) and then...
 ```
-jscodeshift -t /path/to/react-virtualized/codemods/7-to-8/TODO.js source
+jscodeshift -t /path/to/react-virtualized/codemods/7-to-8/rename-components.js source
 ```
 
 ##### 7.24.1

codemods/7-to-8/rename-components.js

@@ -0,0 +1,19 @@
+const renameMap = {
+  FlexColumn: 'Column',
+  FlexTable: 'Table',
+  VirtualScroll: 'List'
+}
+
+module.exports = function transformer (file, api) {
+  const j = api.jscodeshift
+
+  return j(file.source)
+    .find(j.Identifier)
+    .filter(
+      identifier => !!renameMap[identifier.value.name]
+    )
+    .replaceWith(
+      identifier => j.identifier(renameMap[identifier.node.name])
+    )
+    .toSource()
+}