Version 0.1.1 (new root CA certificate)

Release version 0.1.1 (second alpha release)
This release uses the new root CA certificate
(T-TeleSec GlobalRoot Class 2), which is required since 08.03.2018,
instead of the old one (Deutsche Telekom Root CA 2).

Summary of the changes (git log --format=oneline),
the newest changes are at the top:

• Switch to the new root CA certificate

Version 0.1.0 (proof of concept)

Release version 0.1.0 (first alpha release)
This release should already be usable but it doesn't do any error
handling and there's no real user interaction (apart from
username/password input).

Summary of the changes (git log --format=oneline),
the newest changes are at the top:

• Implement the most basic functionality
• Add a very basic GUI
• Add the main activity
• Add the GPLv3 (GPL-3.0) license
• Create the project with Android Studio 3.0.1
• Add a customized gitignore