feature: replace unzip usage with Python's zipfile

[mayeut]

This removes the need to have unzip installed.

fixes #258
closes #312

[mayeut]

tests/unit/test-permissions.zip.xz created with:

mkdir test-permissions
pushd test-permissions 
for i in 0 1 2 3 4 5 6 7; do
	for j in 0 1 2 3 4 5 6 7; do
		for k in 0 1 2 3 4 5 6 7; do
			perm=${i}${j}${k}
			mkdir ${perm}.d
			touch ${perm}.d/f
			chmod ${perm} ${perm}.d
			touch ${perm}.f
			chmod ${perm} ${perm}.f
		done
	done
done
sudo zip -r -0 ../test-permissions.zip .
popd
sudo rm -rf test-permissions
xz -z -e -f test-permissions.zip

[codecov]

Codecov Report

Merging #324 (66d02ac) into master (24fddf5) will increase coverage by 0.28%.
The diff coverage is 93.75%.

@@            Coverage Diff             @@
##           master     #324      +/-   ##
==========================================
+ Coverage   89.07%   89.35%   +0.28%     
==========================================
  Files          23       23              
  Lines        1199     1203       +4     
  Branches      250      254       +4     
==========================================
+ Hits         1068     1075       +7     
+ Misses         82       78       -4     
- Partials       49       50       +1     

Impacted Files	Coverage Δ
auditwheel/tools.py	92.59% <93.75%> (+6.59%)	⬆️

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[lkollar]

Looks good to me. A question on the tests though: why not create the test zip fie in the test suite itself instead of checking the file in? That would make it clearer how the file is created and easier to maintain in case we have to change the input in the future.

[lkollar]

Why is this file compressed twice?

[mayeut]

the zip is 215kB, with xz compression, goes down to 8kB

[mayeut]

A question on the tests though: why not create the test zip fie in the test suite itself instead of checking the file in?

I wanted a single source for that file without wondering if there was an implementation detail in python x.y that would make things flaky.
I can still try to implement this in python & add some kind of check to make sure everything is as expected in the zip file.

[lkollar]

I can still try to implement this in python & add some kind of check to make sure everything is as expected in the zip file.

I've approved the PR. If you still want to give this a go, we could handle it in a separate PR.