Fixes EtherollApp build

• The app complies with the inclusion criteria
• All related fdroiddata issues have been referenced in this merge request
• Builds with fdroid build

---

Recent python-for-android updates requires to:

• use the NDK r19
• update the binary output path
• update buildozer to recent master fixes

This was tested successfully with:

fdroid build --verbose --latest --server com.github.andremiras.etheroll

Which produced the following (truncated) output:

...
DEBUG: buildserver > [DEBUG]:           BUILD SUCCESSFUL in 1m 19s
DEBUG: buildserver > [DEBUG]:           27 actionable tasks: 27 executed

DEBUG: buildserver > [INFO]:    <- directory context /home/vagrant/build/com.github.andremiras.etheroll/.buildozer/android/platform/python-for-android
DEBUG: buildserver > [INFO]:    # Copying APK to current directory
DEBUG: buildserver > [INFO]:    # APK filename not found in build output. Guessing...
DEBUG: buildserver > [INFO]:    # Found APK file: /home/vagrant/build/com.github.andremiras.etheroll/.buildozer/android/platform/build-armeabi-v7a/dists/etheroll__armeabi-v7a/build/outputs/apk/release/etheroll__armeabi-v7a-release-unsigned.apk
DEBUG: buildserver > [INFO]:    # Add version number to APK
DEBUG: buildserver > [INFO]:    # APK renamed to etheroll__armeabi-v7a-release-unsigned-2019.1108-.apk
DEBUG: buildserver > stty: 'standard input': Inappropriate ioctl for device
DEBUG: buildserver > [DEBUG]:   -> running cp /home/vagrant/build/com.github.andremiras.etheroll/.buildozer/android/platform/build-armeabi-v7a/dists/etheroll__armeabi-v7a/build/outputs/apk/release/etheroll__armeabi-v7a-release-unsigned.apk etheroll__armeabi-v7a-release-unsigned-2019.1108-.apk
DEBUG: buildserver > WARNING: Received a --sdk argument, but this argument is deprecated and does nothing.
DEBUG: buildserver > No compiled python is present to zip, skipping.
DEBUG: buildserver > No setup.py/pyproject.toml used, copying full private data into .apk.
DEBUG: buildserver > Applying Java source code patches...
DEBUG: buildserver > Applying patch: src/patches/SDLActivity.java.patch
DEBUG: buildserver > # Android packaging done!
DEBUG: buildserver > # APK etheroll__armeabi-v7a-2019.1108-armeabi-v7a-release-unsigned.apk available in the bin directory
DEBUG: buildserver > INFO: Successfully built version 2019.1108 of com.github.andremiras.etheroll
DEBUG: buildserver > DEBUG: > /home/vagrant/android-sdk/build-tools/26.0.0/aapt dump xmltree build/com.github.andremiras.etheroll/bin/etheroll__armeabi-v7a-2019.1108-armeabi-v7a-release-unsigned.apk AndroidManifest.xml
DEBUG: buildserver > DEBUG: Checking build/com.github.andremiras.etheroll/bin/etheroll__armeabi-v7a-2019.1108-armeabi-v7a-release-unsigned.apk
DEBUG: buildserver > DEBUG: > /home/vagrant/android-sdk/build-tools/26.0.0/aapt dump badging build/com.github.andremiras.etheroll/bin/etheroll__armeabi-v7a-2019.1108-armeabi-v7a-release-unsigned.apk
DEBUG: buildserver > INFO: success: com.github.andremiras.etheroll
DEBUG: buildserver > INFO: Finished
DEBUG: buildserver > INFO: 1 build succeeded
INFO: ...getting exit status
DEBUG: retrieved com.github.andremiras.etheroll_721203008_toolsversion.log
INFO: Retrieving build output...
INFO: [chan 0] sftp session closed.
DEBUG: virtualbox is the sole installed and supported vagrant provider, selecting 'virtualbox'
DEBUG: vm uuid: 0a479117-0213-4d1e-93f7-ced3cefd1684
INFO: suspending buildserver
==> default: Saving VM state and suspending execution...
DEBUG: skip deploying full build logs: not enabled in config
INFO: success: com.github.andremiras.etheroll
INFO: Finished
INFO: 1 build succeeded