Bump library version to 0.3 (currently alpha)

Signed-off-by: Harm Hanemaaijer <fgenfb@yahoo.com>
Shadow bug-fixes

Recognize spherical sectors when checking whether shadow volume is
outside the frustum.

Improve shadow caster/receiver region handling for shadow mapping by
checking shadow receiver AABB against the frustum instead of the
shadow caster AABB.

Signed-off-by: Harm Hanemaaijer <fgenfb@yahoo.com>
Fix shadow mapping with point lights

Fix bug in shadow map shader so that shadow mapping for works again
for point lights using cube mapping.

Signed-off-by: Harm Hanemaaijer <fgenfb@yahoo.com>