Merge pull request #500 from gilesknap/readme-fix

Readme fix

README.rst

@@ -22,6 +22,23 @@ animations, panoramas, movies, effects and collages are also backed up.
 This software is read only and never modifies your cloud library in any way,
 so there is no risk of damaging your data.
 
+WARNING: Index DB Schema Change
+===============================
+
+3.2.4 introduces a change to the index database schema in order to distinguish between
+private albums and shared albums. You will be required to rebuild your index
+database when upgrading to this version or later.
+
+Please use the command line option ``--flush-index`` to rebuild the index database.
+
+This need only be done for the first invocation of the new version.
+
+If you have not done so you will see the error message:
+```
+sqlite3.OperationalError: no such column: IsSharedAlbum
+```
+
+
 Warning: Google API Issues
 ==========================