- Renamed check_query() to db_escape_string().  Commit announced on the mailing list.

- fix issue for mkdir() for versions of php before 4.1.2. closes #11307

by the coding standards, see CODING_STANDARDS.html). I also unified the
format and the location of the $Id$ tag. It starts with "//" and is placed
on the second line in all *.module files, now.

  the file cache.

- add function to allow adding of files from the local filesystem.