installer:get timezone from system first

tower:https://tower.im/projects/8f19f0bf0e754f0b82ef2c24bc230973/todos/ad2ef89cff0e43289d33f7c128bbca2c/#33a54eb348ef4faab99856ffc07ea75d
Change-Id: I2239ce2eb98b29cf49b64c88ab3a670745f93e29
auto sync po files from transifex

Change-Id: Ia77073f410e2621b5ec1b790ed5ebb8de6b07c07