software_spec: GitHub Packages/Bintray fixes.
software_spec: GitHub Packages/Bintray fixes.

- assign the `version` for the `resource` before the `downloader` is
  created
- fix the reference to `Bintray`

claui/brew,MikeMcQuaid/brew,MikeMcQuaid/brew,nandub/brew,MikeMcQuaid/brew,EricFromCanada/brew,nandub/brew,EricFromCanada/brew,EricFromCanada/brew,claui/brew,Homebrew/brew,Homebrew/brew,JCount/brew,JCount/brew,Homebrew/brew,claui/brew,EricFromCanada/brew,MikeMcQuaid/brew,nandub/brew,Homebrew/brew,nandub/brew,JCount/brew,claui/brew,JCount/brew