some usability improvements.

SoundingSoil/app/build.gradle

SoundingSoil/app/src/main/ic_launcher-web.png

...n/java/ch/kentai/android/soundingsoil/BlinkyActivity.java

.../java/ch/kentai/android/soundingsoil/ScannerActivity.java

...ntai/android/soundingsoil/viewmodels/BlinkyViewModel.java

SoundingSoil/app/src/main/res/drawable-xhdpi/biovision.png

SoundingSoil/app/src/main/res/drawable-xhdpi/eth.png

SoundingSoil/app/src/main/res/drawable-xhdpi/nabo.png

SoundingSoil/app/src/main/res/drawable-xhdpi/wsl.png

SoundingSoil/app/src/main/res/drawable-xhdpi/zhdk.png

...Soil/app/src/main/res/drawable/ic_launcher_background.xml

SoundingSoil/app/src/main/res/layout/activity_blinky.xml

...ngSoil/app/src/main/res/layout/activity_splash_screen.xml

SoundingSoil/app/src/main/res/menu/filter.xml

SoundingSoil/app/src/main/res/menu/main_menu.xml

...ngSoil/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml

.../app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml

SoundingSoil/app/src/main/res/mipmap-hdpi/ic_launcher.png

...l/app/src/main/res/mipmap-hdpi/ic_launcher_foreground.png

...ngSoil/app/src/main/res/mipmap-hdpi/ic_launcher_round.png