Lade till prototype i happen "assets"
* camera_android.userprefs: 

* Image.cs: data types changed

* ImageDatabase.cs: datatypes etc changed

* ImageHelper.cs: persist to sql added

* MainActivity.cs: persist to sql
* ImageHelper.cs: using "using" is tricky

* MainActivity.cs:
* prototyp2.tiff:
* camera_android.csproj: