ensure that file permissions are kept for distinfo and data directories

[mboisson]

This addresses https://github.com/MrMino/wheelfile/issues/17

[MrMino]

Thanks, lgtm.

I would like to add some tests to this (most of wheelifle was done using test-first). It would be very helpful if you added it, so that when I actually get back to developing this it would be as easier for me to pull. You can put them into separate test_* file, I'll handle the rest.

[mboisson]

Ok, I realized there were already tests for ZipInfo for dist and data directories, but they were marked as xfail because writestr_distinfo and writestr_data did not propagate zinfo information. Therefore, instead of writing new tests, I fixed writestr_distinfo and writestr_data and generalized the code I wrote using a new internal function _clone_and_rename_zipinfo, which clones the ZipInfo object under a new filename, and used that function in all 3 instances (from_wheelfile, writestr_data and writestr_distinfo). I then unmarked the existing tests from xfail.

[mboisson]

Note that I am unsure about how to run the tests, so there may be some issues.

[MrMino]

@mboisson thank you! This will be the first thing I release as soon as I get back to OSS, along with the other metadata stuff. Sorry for the long wait.

[MrMino]

Superseeded by 7b69c5aa14152abb2785b5a9e9fe56244c000168.