Add deployment documentation for translations.

Task-number: QTBUG-28766

Change-Id: Ibc1b71fde39d344167f7dcecba81e2618c3e4e97
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@digia.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Fix CLANG-warning about unused variable q_ptr.

Change-Id: Ife2e8d38059dfff33f544587f8a8b6f6c8bc2a8b
Reviewed-by: Jarek Kobus <jaroslaw.kobus@digia.com>