- recommend working out of the main tap rather than symlinking, as it
seems to make the instructions shorter/simpler
- add user's fork as a remote of the main tap, and push branch to that
- reference the new brew cask create command
refs #306
this will cause it to show up as a link from incoming pull requests, and
also make the documentation and its change history a little more
first-class with respect to the rest of the project.
big ups to @mkouhia, @passcod, @mwarkentin, and @vincecima for their
work on this document!