doc: prepend vendor names to disambiguate

note as well that Casks which differ only by placement
of hyphens are somewhat ambiguous and to be avoided.
rename Casks which collide on "flux" by vendor

The product from justgetflux.com becomes flux.rb.  The
current flux.rb is renamed the-escapers-flux.rb.  This
resolves having two Cask names which differ only by the
placement of hyphens.
rename Casks which collide on "unison" by vendor

`unison-usenet.rb` becomes `panic-unison.rb`
rename Casks which collide on "webpquicklook"

disambiguate by vendor/developer
Merge pull request #3362 from rolandwalker/prepend_vendor_name_to_disambiguate

Prepend vendor name to disambiguate Casks