* show git branch and hash in About dialog
This additional info will only be shown, if the code is not an official release.
An official release is calculated as follows:
- current commit has a tag
- the tag contains the version number of the package
However, the information will always be printed to the console.
* info will now always be shown in About dialog (if available)
ElectronClient/app/compile-package-info.js: added warning
ElectronClient/app/app.js: push info conditionally to the message array
* use sprintf syntax
