Merge remote-tracking branch \'libxml2/master\' into mymerge

am: 6be36484

* commit '6be36484':
  Release of libxml2-2.9.3
  CVE-2015-8242 Buffer overead with HTML parser in push mode
  CVE-2015-7500 Fix memory access error due to incorrect entities boundaries
  Bug on creating new stream from entity
  Fix some loop issues embedding NEXT
  Detect incoherency on GROW
  Do not print error context when there is none
  Reuse xmlHaltParser() where it makes sense
  Add xmlHaltParser() to stop the parser
  CVE-2015-5312 Another entity expansion issue
  CVE-2015-7497 Avoid an heap buffer overflow in xmlDictComputeFastQKey
  xmlStopParser reset errNo
  Avoid processing entities after encoding conversion failures
  Avoid extra processing of MarkupDecl when EOF
  Reenable xz support by default
  CVE-2015-8035 Fix XZ compression support loop
  Fix parsing short unclosed comment uninitialized access
  Fix an error in previous Conditional section patch
  Correct spelling of "calling"