ENH: pygccxml v1.6.2 (reduced)

This corresponds to commit hash
  cb908d3e9faeff278d2da66149e9db59a2f62d6c
from upstream repository
  https://github.com/gccxml/pygccxml
ENH: Update pygccxml to v1.6.2

Adds python 3 support for pygccxml.

Merge branch 'pygccxml-upstream' into pygccxml-update
(See commit d4624a99ea62221f251e8e77d813289ad441d513)

Change-Id: I7259304fe5e36fa53f04a62ec279caf32612483b
ENH: Add script to update pygccxml from upstream

Change-Id: I6f8d8339e0531e49e5800d2c79423612553cdd08
Merge topic 'pygccxml-update'

a52f78b4 ENH: Add script to update pygccxml from upstream
13e26853 ENH: Update pygccxml to v1.6.2
d4624a99 ENH: pygccxml v1.6.2 (reduced)