* Add LintableFilesVisitor
* Move LintCommand logic into LintOrAnalyzeCommand
to prepare for the upcoming analyze command
* Add AnalyzeCommand (not fully implemented yet in SwiftLintFramework)
* Add analyzerRules configuration member
* Add AnalyzerRule protocol
* Pass compiler arguments to validate/correct
* Add requiresFileOnDisk member to RuleDescription
This will be used by AnalyzerRules because they need a file on disk
to pass in the compiler arguments to SourceKit.
* Exclusively run AnalyzerRules when the Linter has compiler arguments
* Enable testing AnalyzerRules in TestHelpers
* Add ExplicitSelfRule
* Update documentation
* Fix `analyze --autocorrect`
* Improve performance of CompilerArgumentsExtractor
* Fix lint command actually running analyze
* Move File operations in TestHelpers into a private extension
* Add analyzer column to rules command and markdown documentation
* Use a Set literal
* Make AnalyzerRule inherit from OptInRule
* Mention analyzer_rules in readme
* Mention that analyzer rules are slow
The MIT license doesn't require that all files be prepended with this
licensing or copyright information. Realm confirmed that they're ok with this
change. This will enable some companies to contribute to SwiftLint and the
date & authorship information will remain accessible via git source control.
also slightly speed up writing to the cache.
For example, on the Lyft codebase with 1,500 Swift files:
```bash
$ time swiftlint lint --quiet
swiftlint --quiet 3.53s user 0.27s system 388% cpu 0.979 total
$ rm -rf ~/Library/Caches/SwiftLint && time swiftlint lint --quiet
swiftlint --quiet 35.20s user 1.22s system 371% cpu 9.806 total
$ time swiftlint lint --quiet
swiftlint lint --quiet 0.90s user 0.13s system 218% cpu 0.472 total
$ rm -rf ~/Library/Caches/SwiftLint && time swiftlint lint --quiet
swiftlint lint --quiet 31.78s user 1.18s system 360% cpu 9.146 total
```
also remove parallelForEach from SwiftLintFramework's public interface
since calling the GCD API is almost as concise and avoids polluting the
public API.
Finally, also remove the "fast" path for parallelMap since GCD should
do the reasonable thing for us here.
Marcelo Fabri