- prevent creation of a new db with the same name as an existing directory
- Renaming: Do only allow moving files, if $subdirectories==true and the new path is within $directory. So do not allow users to move files out of $directory (or subfolders)
- if there is no db at all and the first db to be created has an illegal extension, also show the error message

git-svn-id: https://phpliteadmin.googlecode.com/svn/source/1.9.3.2@315 c054f44c-0d31-6418-e286-147a9414beb1