WIP Documents the new dedicated commands

Author: raphaelstolt

README.md

@@ -193,6 +193,17 @@ cat .gitattributes | lean-package-validator validate --stdin-input
 
 ### Additional commands
 
+#### Create command
+
+The `create` command will create a `.gitattributes` file in the given directory. This command replaces the `--create` 
+option of the `validate` command. Please migrate to the dedicated commands.
+
+
+#### Update command
+
+The `update` command will update a present `.gitattributes` file in the given directory. This command replaces the `--overwrite`
+option of the `validate` command. Please migrate to the dedicated commands.
+
 #### Init command
 
 The `init` command will create an initial `.lpv` file with the default patterns used to match common repository artifacts.