skype 6.9.59.517

updated skype from 6.8.60.351 to 6.9.59.517
Add cask for Chromatic version 0.2.3
Version bump for Cask: Chromatic (0.2.3 to latest)
Merge pull request #1139 from elseym/chromatic-0.2.3

Add cask for Chromatic version 0.2.3
Merge pull request #1138 from RoyXiang/skype-6.9.59.517

skype 6.9.59.517
Merge remote-tracking branch 'phinze/homebrew-cask/master'