Added required classes for taking and saving a picture refs #2499
added new Class for chose a Picture refs #2498
some small changes, better way for using image as backgrounds refs #2498
Improved Tags and Package structure refs #2499
changing background is ready refs #2498
Passing the Picture File to the ShowPictureActivity refs #2499
Merge remote-tracking branch 'origin/feature/2499-TakingAndSavingPhotos' into feature/2498-ShowPicture

Conflicts:
	AndroidManifest.xml
	src/main/java/io/github/data4all/activity/MainActivity.java
merged with refs #2499 and working together refs #2498
Merge remote-tracking branch 'origin/feature/2498-ShowPicture' into feature/2741-AssembleApplication

Conflicts:
	AndroidManifest.xml
	res/layout/activity_paint.xml
	res/menu/main.xml
	res/values/strings.xml
	src/main/java/io/github/data4all/MainActivity.java