Improve app metadata, include fdroid metadata in repository

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

android/app/src/main/res/mipmap-mdpi/ic_launcher.png

android/app/src/main/res/mipmap-xhdpi/ic_launcher.png

android/app/src/main/res/mipmap-xxhdpi/ic_launcher.png

android/app/src/main/res/mipmap-xxxhdpi/ic_launcher.png

android/gradle.properties

fastlane/metadata/android/en-US/changelogs/0.txt

fastlane/metadata/android/en-US/changelogs/1.txt

fastlane/metadata/android/en-US/changelogs/2.txt

fastlane/metadata/android/en-US/changelogs/3.txt

fastlane/metadata/android/en-US/changelogs/4.txt

fastlane/metadata/android/en-US/changelogs/5.txt

fastlane/metadata/android/en-US/changelogs/6.txt

fastlane/metadata/android/en-US/changelogs/7.txt

fastlane/metadata/android/en-US/changelogs/8.txt

fastlane/metadata/android/en-US/changelogs/9.txt

fastlane/metadata/android/en-US/full_description.txt

fastlane/metadata/android/en-US/images/featureGraphic.png

fastlane/metadata/android/en-US/images/icon.png

fastlane/metadata/android/en-US/short_description.txt