Add GNU Octave 3.8.0-6

[anemator]

There is a problem with uninstall, similar to what many people described in #3322.

[rolandwalker]

Hi! Thanks!

The reason people had problems in #3322 is that uninstall :executable does not accept App bundles. Instead, it accepts a command-line executable binary (and optionally arguments to that executable).

The best way to write an uninstall stanza is to use uninstall :pkgutil => <bundle-id>. To find out the relevant bundle-id/s for Octave, the easiest method is to install Octave, and then run

$ /usr/local/Library/Taps/caskroom/homebrew-cask/developer/bin/list_recent_pkg_ids

There is detailed doc on the :pkgutil key in CASK_LANGUAGE_REFERENCE.md. Let us know if you need any help.

[anemator]

I think that should do the trick.

[rolandwalker]

Great, much appreciated!