This required various changes to various parts of the infrastructure (mostly
using paths to finding the "root project" of any given object throughout).
Now theoretically infinite projects can be opened and accounted for at any
given time.
OCIO config was set on a per-project basis, but we were using a singleton for
the ColorManager that would break if more than one project was ever open.
Now the ColorManager belongs to the Project and is always accessed through the
Project.
itsmattkc