Password change email needs more context

When a user's password is changed, e.g. via web-interface by admin or by himself, an email is sent to the user's email address:

Subject: ownCloud password changed successfully
Body:

Password changed successfully

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ownCloud - A safe home for all your data
https://owncloud.org

Improvements:

• This email should at name the owncloud server on which the change happened.
• Exact Date and Time of the Change.
• Remote IP address of the web-browser causing the change.
• username causing the change.