Refactor helpers/container/service pkg

The following discussions from !1680 (merged) should be addressed:

• @steveazz started a discussion:

  Let's follow the Go practice using camleCase

  	referenceRegexpNoPort := regexp.MustCompile(`^(.*?)(|:[0-9]+)(|/.*)```suggestion:-0+0
  )

• @steveazz started a discussion:

  Named returns are sometimes hard to debug/understand and maintain, also it's suggested to avoid them for large functions. Can we try and remove this?

  ---

  Having a function parse strings with regex and doing manipulation is not always straight forward. I think we should add a comment to this explaining that it will transform an example string into some struct. For example:

  Prase `golang:1.13` into a struct .....

• @steveazz started a discussion:

  Should this be a constant instead?