[libxml2] (3 commits) Non-fast-forward update to branch ddkilzer/fix-missing-xmlBuf-xmlBuffer-NUL-terminators

[David Kilzer <ddkilzer src gnome org>]

The branch 'ddkilzer/fix-missing-xmlBuf-xmlBuffer-NUL-terminators' was changed in a way that was not a 
fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  78a4920... Fix missing NUL terminators in xmlBuf and xmlBuffer functio

Commits added to the branch:

  c14cac8... xmlBufAvail() should return length without including a byte (*)
  a6df42e... Fix integer overflow in xmlBufferDump() (*)
  e461bb2... Fix missing NUL terminators in xmlBuf and xmlBuffer functio

(*) This commit already existed in another branch; no separate mail sent