Make SceneGraph::Camera as Node + FieldOfView animatable

Make SceneGraph::Camera as Node + FieldOfView animatable

Previously, SceneGraph::Camera was not a SceneGraph::Node.
If we try to animate property of Camera, then
we use some PropertyBase s.t. PropertyOwner(==Node) doesn't owned.

To fix this logical unmatched issue, we make SceneGraph::Camera
as sub-class of SceneGraph::Node.

Moreover, We make Camera's FieldOfView Animatable.

After this patch merged, we try to refactor Camera's properties
and make them animatable.

Change-Id: I184f75b51a2152aea52879adc1e783cea7d190a0
Signed-off-by: Eunki, Hong <eunkiki.hong@samsung.com>