ringtone: add new page for selecting ringtones

ring-android/app/src/main/AndroidManifest.xml

...-android/app/src/main/assets/ringtones/1 AfroNigeria.opus

ring-android/app/src/main/assets/ringtones/10 UrbanTrap.opus

...-android/app/src/main/assets/ringtones/2 AfroNigeria.opus

...droid/app/src/main/assets/ringtones/3 AcousticGuitar.opus

...droid/app/src/main/assets/ringtones/4 ElectricGuitar.opus

...ndroid/app/src/main/assets/ringtones/5 AcousticIndia.opus

ring-android/app/src/main/assets/ringtones/6 RingSoft.opus

ring-android/app/src/main/assets/ringtones/7 RingTribal.opus

...-android/app/src/main/assets/ringtones/8 RingFirefly.opus

...android/app/src/main/assets/ringtones/9 ElectroCloud.opus

...d/app/src/main/java/cx/ring/adapters/RingtoneAdapter.java

...id/app/src/main/java/cx/ring/client/RingtoneActivity.java

...a/cx/ring/dependencyinjection/RingInjectionComponent.java

.../main/java/cx/ring/fragments/MediaPreferenceFragment.java

...main/java/cx/ring/fragments/MediaPreferencePresenter.java

.../src/main/java/cx/ring/fragments/MediaPreferenceView.java

.../app/src/main/java/cx/ring/navigation/AccountAdapter.java

ring-android/app/src/main/res/drawable/baseline_add_24.xml

...rc/main/res/drawable/baseline_notifications_active_24.xml