Share ayah: append new line after last ayah

Ayah(s) and sura label(s) get visually confusing in LTR (e.g., non-Arabic) context. This change separates the ayah(s) and sura label(s) with a new line.

Additionally,
 * separated the code into clearer blocks and removed unnecessary if checks (or moved into inner scope)
 * replaced deprecated android.text.ClipboardManager with new one with backward compatibility check