Many new features and fixes.

Migrated to the AndroidX extra library.

Quoted-printable email and Encoded-word (RFC 2047) decoding with Apache Commons.

A WebView that displays emails in html, in offline mode.

Updated the internal SQLCipher database to v4.4.0.

Remowrked password dialog.

Mitigated Context leakages.

Open account drawer by pressing on background of app.

Added translations - French, German, Spanish.

Updated animations.

Beeping sound uses system message default.

Long-press on message thread offers the option for direct reply.