Allow multiple snippets directories

Please allow multiple directories to be listed for "snippetsdir". I like keeping my snippet files separate from the default Cobbler ones. Initially I added a symlink from the default snippets directory to my snippets. But then I have to specify the directory path for each snippet, and the hierarchy search method for per_profile etc. doesn't work under that directory. Then I changed the settings to point to my snippets directory instead of the default, and copied Cobbler's default snippets to my directory. Now I don't need to specify a path to snippets, and the hierarchy works. But then everything is mixed up, and if Cobbler's snippets change in a later release, it's easy to forget to update them. That's why it would be nice to be able to use a PATH or LIB style method to allow multiple directories to be specified for snippets. Then they don't need to be mixed up, yet the hierarchy search could work in all directories.