* Clean-up EntityManager a bit
- use tsl::robin_set instead of std::set (which should have been unordered::set
anyways).
- getListeners() now returns a vector which avoids to traverse a set twice.
Turns out that copying the set wasn't as efficient as I thought.
* Improve jobsystem a bit
We recently added a job reference counting mechanism, but we were a bit
too aggressive about taking/release references.
Also make the API more complete by adding explicit retain/release,
which is needed to allow several threads to wait on the same job.
Also improve futex code by inlining it.
computeLightTree() takes a list of light as
a bitfield and produces a depth-first
binary tree array that can be used to efficiently
check which lights volumes contain a given z
coordinate in screen space.
Currently computeLightTree() produces the array
locally on the stack, which isn’t useful, but
before we can make use of it, a lot of other
things have to happen.
