Add "open-with-sublime-text"

Takes logic from "open-with-sublime-text-2", however, allows for using Sublime Text (v3) since the .app-name changed
Update README.md to match correct .app-name
Update alfredworkflow to also allow keyword 'st'
Merge branch 'refs/heads/philipptempel-open-with-sublime-text'
Open With Sublime Text v3: Remove additional keyword; update author information, Readme, screenshots.