v0.3.0

New Feature

• mamiya build --push option to automatically pushing built package
  after its build #26

• Script#run now supports setting environment variables via trailing hash #29

  run "printenv", "MYENV", "MYENV" => "Hello"

Enhancements

• Ensure string arguments on spawning processes #24
• Formatted Script#run log (aligned spaces)

Bug fixes

• Removed duplicated key warning #21