afparse will eventually be able to support pipelines like: gst-launch filesrc location=file.aiff ! afparse ! osssink

Original commit message from CVS:
afparse will eventually be able to support pipelines like:
gst-launch filesrc location=file.aiff ! afparse ! osssink

However at the moment it doesn't, because the public function afOpenVirtualFile isn't actually implemented yet. I implemented it with the audiofile CVS but it now segfaults the very first time one of the virtual file callbacks is called.

So, I'm committing this for posterity but it is not being built.  Hopefully the audiofile lib will be released with working virtual file support soon.