Add SRWare Iron Latest

I added a cask for the browser "SRWare Iron".

It is based on chromium, but respects the privacy more of the user.
On the Homepage you can find more details about that.
Would you mind rephrasing this as `# Renamed for clarity: app name is inconsistent with its branding.` for [consistency with the examples](https://github.com/caskroom/homebrew-cask/blob/master/doc/CASK_LANGUAGE_REFERENCE.md#target-should-only-be-used-in-select-cases)?