Casks with non-preferred download sources

[rolandwalker]

Refs #6570, #6567, #6569

Probably most of these are not "solvable", but should be checked for a better download source, and commented appropriately if we are using the best available.

In cases where the homepage/url combination is a forum posting and dropbox link, perhaps a caveat is warranted, because there is no identifiable vendor standing behind a binary, and no entity who would lose reputation in the event of compromise — except us.

Casks using dropbox

• abgx360.rb
• actotracker.rb
• clipmenu.rb
• geektool.rb grep error per @vitorgalvao
• giffun.rb
• jsonlook.rb
• lincastor.rb
• monochrome.rb
• ninjablocks.rb
• rftg.rb
• tactor.rb
• tagoman.rb
• thaiwitter.rb
• uber-network-fuser.rb

[vitorgalvao]

Checked all the dropbox ones.

monochrome is now paid, and can only be downloaded after paying, so it was removed. rftg now has a non-dropbox link, and has been corrected. geektool doesn’t have a dropbox download url, but a dropbox appcast url instead.

All the others are confirmed as having dropbox as the official download source on the website, and will be labeled as such in #6577.