Fix #11240 (#11995)

* extends mkdirs with permissions for intermediate folders

Does not use os.makedirs mode parameter because its behavior is changed
with Python 3.7 (it ignores it for intermediate dirs), and moreover it
was not possible to set different modes for newly-created folders
and leaf folder.

reference:
- https://bugs.python.org/issue19930
- https://docs.python.org/3.7/library/os.html#os.makedirs

* comment mkdirp step easing code understanding

* revert mkdir to default for package metapath

since metapath is nested in package folder, there is no need
to specify permissions for intermediate folders because the prefix
already exists.

* comment create_install_directory package modes

0 files changed, 0 insertions, 0 deletions