[FFe] Re-enable ClickPad support by default.

I'm not sure if this requires a FFe, but I'm filing one out of an abundance of caution.

A few weeks ago we enabled ClickPad functionality by default. See bug 932947 for details. We ended up disabling it by default because it broke "click actions", e.g. physically clicking with two touches to generate a right click.

Precise currently has a snapshot of upstream synaptics master branch. Our requirement for multitouch support forces us to follow master because there is no previous release of synaptics with touch support. Upstream, ClickPad support has also been merged, and the click actions interference has been rectified. Performing a click action is now possible on a ClickPad.

Upstream is close to releasing a new version of Synaptics. We will be updating to it. Our options are:

* Update to Synaptics release and have ClickPad support enabled by default
* Update to Synaptics release and distro-patch it to disable ClickPad support by default due to the Precise feature freeze

The ClickPad support is well tested in Ubuntu. The only known issue is the interference with click actions. Now that this has been resolved, I believe we should follow upstream and re-enable ClickPad support by default.

I have personally tested the ClickPad vs click action handling on my Apple Magic Trackpad. The resolution for the interference may be found at: http://cgit.freedesktop.org/xorg/driver/xf86-input-synaptics/commit/?id=420e0abef663729b3ce6e9d26360e616b7270ba6. I believe the fix is small, well contained, and the likelyhood of regression is minimal.

The packages are built and available for testing in ppa:chasedouglas/clickpad.