Release v1.4.0 · ruby/logger

What's Changed

Dont run bundle exec rake when running tests in CI by @colby-swandale in #5
Add basic description and examples to the README by @colby-swandale in #4
Dont lock bundler to a specific version by @colby-swandale in #9
Remove files that dont need to be included in gem releases by @colby-swandale in #7
Say that logger requires ruby >= 2.3 by @segiddins in #12
Add support for changing severity using bang methods. by @ioquatix in #15
README.md: Run tests that defined on a specific line by @sonots in #16
Fix to use logger and test-unit in this repo by @sonots in #17
split logger classes/modules into separate files by @sonots in #18
Prefer require_relative, it's a little bit faster. by @ioquatix in #20
Fix testing example to use --name option by @sonots in #24
Enable frozen_string_literal: true in logger.rb. by @ioquatix in #23
frozen_string_literal: true by @sonots in #26
GitHub pages by @sonots in #28
CI: Drop unused setting by @olleolleolle in #29
Set filename when initializing logger with a File object by @jeremyevans in #30
Add option to set the binary mode of the log device by @rafaelfranca in #33
Custom test library replace to test-unit gem by @komagata in #32
Fix typo by @XrXr in #34
Avoid creating [] and "" when logging an Exception that has no backtrace by @amatsuda in #36
Backport test library from ruby core directly. by @hsbt in #35

Full Changelog: v1.3.0...v1.4.0