Running `rake install` always resulted in these warnings:
```
WARNING: open-ended dependency on clocale (>= 0) is not recommended
if clocale is semantically versioned, use:
add_runtime_dependency 'clocale', '~> 0'
WARNING: open-ended dependency on filesize (>= 0) is not recommended
if filesize is semantically versioned, use:
add_runtime_dependency 'filesize', '~> 0'
WARNING: open-ended dependency on manpages (>= 0) is not recommended
if manpages is semantically versioned, use:
add_runtime_dependency 'manpages', '~> 0'
WARNING: open-ended dependency on rainbow (>= 0) is not recommended
if rainbow is semantically versioned, use:
add_runtime_dependency 'rainbow', '~> 0'
WARNING: open-ended dependency on diffy (>= 0, development) is not recommended
if diffy is semantically versioned, use:
add_development_dependency 'diffy', '~> 0'
WARNING: open-ended dependency on rake (>= 0, development) is not recommended
if rake is semantically versioned, use:
add_development_dependency 'rake', '~> 0'
WARNING: open-ended dependency on ronn (>= 0, development) is not recommended
if ronn is semantically versioned, use:
add_development_dependency 'ronn', '~> 0'
WARNING: open-ended dependency on rspec (>= 0, development) is not recommended
if rspec is semantically versioned, use:
add_development_dependency 'rspec', '~> 0'
WARNING: open-ended dependency on rspec-its (>= 0, development) is not recommended
if rspec-its is semantically versioned, use:
add_development_dependency 'rspec-its', '~> 0'
WARNING: open-ended dependency on rubocop (>= 0, development) is not recommended
if rubocop is semantically versioned, use:
add_development_dependency 'rubocop', '~> 0'
WARNING: open-ended dependency on rubocop-rspec (>= 0, development) is not recommended
if rubocop-rspec is semantically versioned, use:
add_development_dependency 'rubocop-rspec', '~> 0'
WARNING: open-ended dependency on rubygems-tasks (>= 0, development) is not recommended
if rubygems-tasks is semantically versioned, use:
add_development_dependency 'rubygems-tasks', '~> 0'
WARNING: See http://guides.rubygems.org/specification-reference/ for help
```
- use pessimistic version constraints for all dependencies in the gemspec
* add `--sort=WORD` option, which sorts by modification "time" or not at all
* add short option `-U` to mean `--sort=none` (`ls` compatibility)
* `-t` now has the same effect as `--sort=time` which is also mentioned in the
post install mesage
* add checks for `--sort=time` and `--sort=none` to .travis.yml
* Add spec/support folder
* Add YamlSortChecker to check if yaml files are sorted
* Add Diffy as a development dependency
* Add spec file for all yaml config files for sorting
