This directory can hold registry configuration snippets. Any PHP file (*.php)
is read; all other files are ignored and so are for information only. Snippets
can contain anything that would go in registry.php - one or more applications,
tree blocks, conditionals, etc.

Scripts that install or update files in this directory should always touch()
the registry.d directory after completion to ensure that its modification time
has changed; that way Horde will know to drop any cached configuration
information.