recast tests to refer to "app" instead of "link"

and "activate" instead of "link" as a verb, in messages,
test names, comments, variable names.

No functional change.
remove support for `link` artifact

* `app`, `suite`, and `artifact no longer implemented as
  synonyms for `link`
* backward-compatible code/comments removed
* creates class `Cask::Artifact::Suite`
* updates `brew cask info` to show specific artifact type
* fixes stray "Generic artifact" messages
Upgrade Owncloud to v1.6.4
Add Voxox latest
add munki
Upgrade AudioMate to 2.1.2
Merge pull request #7065 from rolandwalker/remove_link_stanza

remove support for `link` artifact
Add Futuniuniu.app v2.14.316
Add Snapped for Mac Beta v0.1.5

There is no stable version of this software yet.
Merge pull request #7085 from exherb/munki

add munki
Merge pull request #7082 from rixth/snapped

Add Snapped for Mac Beta v0.1.5
add atom shell
Update Bowery.app to version 3.2.11
Merge pull request #7078 from exherb/atom-shell

add atom shell
Update Android Studio to 0.8.14
Merge pull request #7086 from vinkla/bowery

Update Bowery.app to version 3.2.11
Merge pull request #7075 from mpra/owncloud-update

Upgrade Owncloud to v1.6.4
Merge pull request #7076 from inz/voxox

Add Voxox latest
Merge pull request #7079 from dlackty/android-studio-0814

Update Android Studio to 0.8.14
Merge pull request #7081 from kuno/futuniuniu

Add Futuniuniu.app v2.14.316