user scaffold: change password, view change email

On the edit page empty password means password is not set. This means
that admin can create a user without a password. That user cannot log
in, but can ask for password change token to his email, and then
set the password.

That is pretty neat.

In addition, 'new user' button is now on top, as list might be long.

Signed-off-by: Zeljko <zeljko@zwr.fi>
user can set/change his name

This overrides Devise views for new user and editing own
profile. Both views will be developed more.

To change other Devise views, execute

    rails g devise:views

select 'n' for no when asked to overwrite previously modified
files. When done modifying some views, delete others, they will
keep coming from Devise gem.

Signed-off-by: Zeljko <zeljko@zwr.fi>