Feature/support for excluding with glob

[xzeror]

Addressing issue #1220. Added support for excluding files using globs.
For example, if you want to exclude all test files in project you can add following line into your .swiftlint.yml:

excluded:
  - ./**/*Test?.swift

[SwiftLintBot]

	2 Errors
🚫	Please rebase to get rid of the merge commits in this PR
🚫	Could not build branch

	1 Warning
⚠️	Big PR

Generated by 🚫 Danger

[jpsim]

Thanks for your work on this! A few thoughts:

1. If we support globbing in one place where we take paths, we should support it everywhere we take paths. This includes the included configuration key, maybe other places too, you'll have to look to determine where else it might apply.
2. We don't often add external dependencies to SwiftLint, and doing so should be weighed very carefully. In this case, I have a few concerns:
   1. The dependency is a fork of another project. Is the fork the canonical version of the project? If not, why is the original project not being used?
   2. What signs are there that we can rely on this being actively maintained? Both the fork and the original repo have 0-5 GitHub stars and I can't find any other projects using them.
   3. Tests appear to be minimal, but at least there are some.
   4. What alternatives do we have? Is there a well-regarded C-library that we could wrap in a Swift API?

[codecov-io]

Codecov Report

Merging #1712 into master will increase coverage by 0.22%.
The diff coverage is 91.27%.

@@            Coverage Diff             @@
##           master    #1712      +/-   ##
==========================================
+ Coverage   87.61%   87.83%   +0.22%     
==========================================
  Files         214      220       +6     
  Lines       10534    10848     +314     
==========================================
+ Hits         9229     9528     +299     
- Misses       1305     1320      +15

Impacted Files	Coverage Δ
...iftLintFramework/Extensions/String+SwiftLint.swift	69.64% <100%> (+6.67%)	⬆️
.../SwiftLintFrameworkTests/Glob+SwiftLintTests.swift	100% <100%> (ø)
...Framework/Extensions/NSFileManager+SwiftLint.swift	81.81% <100%> (+11.22%)	⬆️
...ework/Extensions/Configuration+LintableFiles.swift	83.33% <100%> (-1.29%)	⬇️
Carthage/Checkouts/Glob/Sources/Glob.swift	88.49% <88.49%> (ø)
Source/SwiftLintFramework/Rules/CustomRules.swift	94.82% <0%> (-3.45%)	⬇️
...s/SwiftLintFrameworkTests/ConfigurationTests.swift	91.97% <0%> (-2.82%)	⬇️
.../SwiftLintFrameworkTests/SourceKitCrashTests.swift	81.35% <0%> (-0.62%)	⬇️
Tests/SwiftLintFrameworkTests/RulesTests.swift	100% <0%> (ø)	⬆️
... and 11 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 3bfad6c...22d5188. Read the comment docs.

[xzeror]

Hi.

1. I thought about it. Supporting globs in all places could be done later. This PR resolves original ticket and common problem of excluding test files from SwiftLint when they lay in the same place with code. It would be really great if we can ship this MVP to users.
2. Yeah. Adding it as dependency was not easy =)
   i. Original project could not be used because the author doesn't want to add Carthage and CocoaPods support. You could read our discussion here
   ii. I maintain my fork at the moment and expect to do so in the future.
   iii. I'll try to add some tests. What target coverage should I achieve?
   iv. Glob is lightweight wrapper around glob stdlib call already. Should we search for another more lightweight library? I don't think so. Should we use direct stdlib call in SwiftLInt? No. We will need wrapper around it to abstract C structures. Should we incorporate Glob.swift into SwiftLint directly? Maybe. That should be maintainers decision.

[xzeror]

@jpsim could you review my recent changes please?

[shyambhat]

Is there anything I can do to help push this PR forward?

I have no idea what Glob is, but I really think the ability to exclude files with a regex is invaluable.
We integrated SwiftLint into a five year old codebase and it's been almost a week that we've been fixing existing lint warnings. The hundreds of test files in the project are placed in the same hierarchy as the code being tested and having regexes to exclude these files will save us probably another week of fixing warnings.

[tschob]

Are there any plans to continue or replace this PR?

[jpsim]

If this is to be considered, the next steps are to rebase the PR (no merge commits please) and have it pass all CI checks.

[norio-nomura]

Carthage/Checkouts/Glob should be submodule instead of embedding.

[keith]

I've implemented an alternative to this here: #2316

[keith]

This has been merged in #2316 and is part of 0.27.0. I think we can close this PR