add stage selection

[jay2u8809]

Contents

• you can select stage with exclude or include keyword
  • if keyword(exclude or include) is empty, you send slack message to all stage
  • if stage is on both sides, include takes precedence
• example

  •  custom:
       serverlessDeployHistory:
         exclude:
           - dev
           - qa
         include: 
           - production
         slack:
           webhook: 'https://hooks.slack.com/services/~'
           title: 'Sample Deploy History'

[jay2u8809]

fix yaml

• remove exclude, include fields

 custom:
   serverlessDeployHistory:
     stage:
       - dev
       - qa
     slack:
       webhook: 'https://hooks.slack.com/services/~'
       title: 'Sample Deploy History'