Upgrade samples to Android Pie (9.0)

[TimLariviere]

Partial cover of #442

Update the samples to compile for Android Pie (9.0) instead of Oreo (8.1).
Also samples now start support at Android Lollipop 5.0 (API Level 21) instead of Android KitKat 4.4

This is required to be able to use Shell and Visual.

[SergejDK]

Looks good so far but currently the Calculator App does not work anymore. Can't make it work on my device (Motorola G6 Plus). Don't know if it is only me.

EDIT:
Works now. Configurationmanager needed to provide Calculator.Droid (wasn't set as porvided like the other projects); rebuild and restart after this worked.

So all good!

[SergejDK]

Merging it now.

[TimLariviere]

Works now. Configurationmanager needed to provide Calculator.Droid (wasn't set as porvided like the other projects); rebuild and restart after this worked.

@SergejDK I'm not sure to understand.
What do you mean by "ConfigurationManager needed to provide Calculator.Droid"?

[SergejDK]

@TimLariviere have it on german so i hope the follwoing screenshot shows what i mean:

[SergejDK]

the right column i think translated should be "provided" or "supplied"...
If you check this it works.

[TimLariviere]

Ah ok. In English, the columns are "Build" and "Deploy".
So makes sense, it weren't working.

Visual Studio prevented the sample to be deployed on your device.