added build and install information

README.md

-# rosetta_migration_plugin_dummy
+Rosetta MigrationPlugin Dummy
+=============================
+
+Dummy for a Rosetta MigrationPlugin that just copies original file to new file.
+
+Howto build
+-----------
+
+	# change to plugin source code directory
+	$# cd ~/rosetta_migration_plugin_dummy
+
+	# create JAR file
+	$# jar cf rosetta_migration_plugin_dummy.jar .
+
+Howto install
+-------------
+
+1. Open your Rosetta instance and login
+2. Navigate to "Administer the system -> Plug-In Management -> Custom -> Add Plug-In Instance"
 
-Dummy for a Rosetta MigrationPlugin that just copies original file to new file
\ No newline at end of file