Upgrade path for CouchDB 1.x to 2.x on macOS?

I recently downloaded Apache CouchDB 2.1 installer for macOS from the official [website](http://couchdb.apache.org#download) . I already had CouchDB 1.7 installed via Homebrew Cask. After installing CouchDB 2.1, I started observing some problems, like [Local CouchDB on Mac Opens New Browser Tab Every 5 Seconds](https://dba.stackexchange.com/questions/162090/local-couchdb-on-mac-opens-new-browser-tab-every-5-seconds) . Other issues include inconsistent environment variables and ports in use. It appears that the macOS is unsure about the version of CouchDB installed and both the versions are running concurrently. I figured, that a probable reason could be that CouchDB 1.7 was installed via Homebrew Cask, while Apache CouchDB was installed from the downloaded installer as it is not yet available via Homebrew Cask. They have your database migration covered, but not an 1.x-to-2.x upgrade path for the application itself on macOS. I uninstalled Apache CouchDB 2.1 and killed the daemon that it left running. CouchDB 1.7 works fine after that. How do I perform an upgrade in this scenario?