Remove URL normalisation

[ivanayov]

As a target path is a URL path it's not correct to consider it as
interchangeable with a filepath within every operation system. The
unquote is also removed as the ngclient cannot assume correctly
which encoding is intended and which not

Fixes#1483

• The code follows the Code Style Guidelines
• [n/a] Tests have been added for the bug fix or new feature
• [n/a] Docs have been added for the bug fix or new feature

[jku]

tuf/download.py is legacy code base, should not be touched.

The other failures are all in test_updater_ng: my first guess would be the test setup is broken: maybe the test setup uses local file paths as URL parts.

[coveralls]

Pull Request Test Coverage Report for Build 1490229889

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+1.0%) to 98.47%

---

Totals
Change from base Build 1476295870:	1.0%
Covered Lines:	3280
Relevant Lines:	3300

---

💛 - Coveralls

[jku]

I really dislike hard coding OS specific path separators even in test code... but it looks like not doing that would mean we'd have to make the test infrastructure simpler, which is likely a bigger task and requires more infrastructure context.

So... maybe we take this as a win (removing hard coded OS specific path separators from actual library is still a big improvement, even if we just move them to tests), and move on.

@sechkova mind having a look, any opinions?

[sechkova]

I agree with you, I'm ok with changing the tests like this for now. I only have one comment about test_fetcher_ng.

[jku]

marking "request changes" for @sechkovas basename finding: leave a comment if it turns out to be actually necessary

[ivanayov]

@jku@sechkova you've been right. Probably test_fetcher_ng used to fail due to some other change that's been removed now. I discarded the changes there.

[jku]

Thanks!