Rename field Email and Password: strings.xml

[Andreymlc]

Почта -> Email Пароль -> Введите пароль

[ImmortalIdiot]

This was done in the last pull request. In my comment, I meant that in the next tasks you should doing do exactly what is written in the task. For example: Task: add a nickname field to the fragment_registration.xml. So you should add the nickname field, but you don't change the previous design.