Enhance swagger documentation and UI mechanism

[seokho-son]

Enhance swagger documentation and UI mechanism.

If you define (source) SELF_ENDPOINT in setup.env,
you can access Swagger UI from outside.

# Set SELF_ENDPOINT, if you want to access Swagger API dashboard from outside.
# Ex) export SELF_ENDPOINT=xxx.xxx.xxx.xxx:1323
export SELF_ENDPOINT=localhost:1323

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 Multi-cloud infrastructure managemenet framework
 ________________________________________________
 
 
 Repository: https://github.com/cloud-barista/cb-tumblebug
 
 
 [Access to API dashboard] username/password: (xxxxxx/xxxxxxxxx)
 http://xxxxxxxxxx:1323/tumblebug/swagger/index.html?url=http://xxxxxxxxxx:1323/tumblebug/swaggerActive
 
⇨ http server started on [::]:1323
⇨ grpc server started on [::]:50252