Update gem spec for `mruby-sleep`
To align the spec like any other core mrbgems:
Delete `spec.version`
Set `spec.summary`
MODIFY
mrbgems/mruby-sleep/mrbgem.rake
mrbgems/mruby-sleep/mrbgem.rake
MRuby::Gem::Specification.new('mruby-sleep') do |spec|
spec.license = 'MIT'
spec.authors = ['MATSUMOTO Ryosuke', 'mruby developers']
- spec.version = '0.0.1'
+ spec.summary = 'Kernel#sleep and Kernel#usleep'
end

Update gem spec for `mruby-sleep`

To align the spec like any other core mrbgems:
- Delete `spec.version`
- Set `spec.summary`