New Feature: Set Alarm/Reminder before actual Event.

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Add new event
2. By now it is possible to set alarm only at actual date/time of event
3. It is useful to be able to set alarm before actual event should happen

What is the expected output? What do you see instead?
Alarm e.g. 3 hours ahead so that it can remind me about e.g. appointment.

What version of the product are you using? On what operating system?
Android 4.0.4

Please provide any additional information below.
It is already in standard google calender app.

Original issue reported on code.google.com by szmas...@googlemail.com on 30 Nov 2012 at 7:36