Merge branch 'release/v2.11.2' into develop
Add missing header.
Fix typo.
Make physics optional.
Fix order of includes.
Adapt to namespace changes in guacamole.
Fetch utils module from attic.
Add avango-utils module.
Wrap gua::math::BoundingSphere.
Add Trackball.
Remove SConscript.
Bump version.
Merge branch 'release/v2.11.3'