Hi!

This directory is used to store development stuff like configuration files,
documentation etc. If you're not a developer you shouldn't mess with this
directory and its content.

README.txt
  This file.

UPGRADE.txt
  A file where all incompatibilities between release should be noted.

scripts/
  some useful scripts

GNUmakefile
mk/
  A handy Makefile to generate doc, stats etc.

db/
  Store the migration files.

doxygen/
  Store the doxygen config and generated stuff if any.

phpmd/
  PHP Mess Detector report directory.

gitstats/
  gitstats report directory.