Memo Player: learn languages

Jun 1, 2019

ver. 2.1.0: add a setting of volume criteria of skip-silence
ver. 2.0.18: show sleep button easier
ver. 2.0.14-15: bug fix on playing in the background for android 8 and 9
ver. 2.0.13: add a storage permission request dialog
ver. 2.0.12: add EU users consent. increase min API level from 10 to 14
ver. 2.0.11: add privacy policy
ver. 2.0.0: improved design
ver. 1.4.0: improved layout