api06: diff upload: don't read the whole request into memory.
api06: diff upload: don't read the whole request into memory.

Note: libxml-ruby-0.5.4 will segfault on this:
https://rubyforge.org/tracker/index.php?func=detail&aid=20117&group_id=494&atid=1971



tillmo/do-roam,tillmo/do-roam,tillmo/do-roam,tillmo/do-roam,tillmo/do-roam,tillmo/do-roam