GLES3.0 (and GL4.1) need informations about the uniform block bindings
because they don't allow to do that setup in the shaders. So we store
that information in the material blob and retrieve it on the filament
side in Material. This information is passed to Program so it can
create the bindings.
Prior to this change, this information was set by Material itself, but
this ment we had two places where these bindings were hardcoded.
The bulk of the change is to add a new material chunk which stores an
array of {name, binding}, retrieve it on the Material side and pass it
to Program.