[pinpoint] Clock in clutter view

[Daniel Garcia Moreno <danigm wadobo com>]

Hello,

Hello, I've just added a clock to pinpoint clutter renderer to view
the time elapsed in presentation. You can view the diff in github [1]

Do you think this is an useful feature that could be added to
pinpoint? The main idea for the clock is for presentations with
limited time, to control in every moment how many time do you spend in
the presentation, and every one in room can view too.

[1] https://github.com/danigm/pinpoint/commit/f711e9fb572ab36f053280e922bc06e864adb7a4