DiffMerge 4.1.0-534

Update DiffMerge
update skim to v1.4.5
Merge pull request #1201 from jokester/skim_v1.4.5

update skim to v1.4.5
updated macvim link
Merge pull request #1202 from kal444/master

updated macvim link
Add KeyboardCleanTool
Skype latest

Update Skype to grab latest version
Merge remote-tracking branch 'phinze/homebrew-cask/master'