Hides Jetpack for all non admin users.
Hides the menu page as well as the icon in the admin bar.
Please Notice (!)
No one but admins will see that you use Jetpack.
No one will know.
If you want only the page to be hidden but not the icon, contact me or
just remove everything from line 37 till the end in jp-rm-jpmenu.php
Simple and short, originally made by http://profiles.wordpress.org/jeherve