[Libguestfs] [PATCH nbdkit filters-v3 0/7] Introduce filters.

[Richard W.M. Jones]

This is still tentative and needs a lot of work, but:

 - partition filter works, supporting MBR & GPT

 - prepare and finalize methods fixed

 - open method can now be changed (allowing readonly flag to be modified)

 - thread_model can be limited

I believe I made most of the changes which were previously suggested
in email.  I think the only one I didn't was preventing inclusion of
both <nbdkit-plugin.h> and <nbdkit-filter.h> in the same file.

Rich.