add an empty line after date to RecentChanges, so that if all files of that day are...

add an empty line after date to RecentChanges, so that if all files of that day are deleted, each date remains a paragraph on its own.

git-svn-id: svn://svn.code.sf.net/p/phpwiki/code/trunk@149 96ab9672-09ca-45d6-a79d-3d69d39ca109