Everyone loves writing documentation! :D
Please update the dates in the copyright notices in each of the files you have modified, if needed.
Please update the file ChangeLog with a summary of which files have been changed, along with what the changes were for.
If your change includes new files please update the MANIFEST.wiki in the directory containing the new files.
If your change is not trivial please take a look to the appropriate architecture page in the wiki. Maybe it is needed to update the page with more information?