@BrettHemes already mentioned ur_modern_driver. I'll answer your question:
Is there plans to develop ROS Kinetic version for driver, with compatibility with moveit planner?
ur_driver is in maintenance mode, it will no longer be developed, and we recommend (perhaps urge is better word) to use ur_modern_driver instead. Its author has worked hard to make sure ur_modern_driver can be used as a drop-in replacement for ur_driver.
Note: I wrote ur_driver, not universal_robot. The other packages in the repository are not deprecated.
So your question becomes:
Are there plans to develop ROS Kinetic version of ur_modern_driver, [..]
As mentioned by @BrettHemes, there is a user-contributed fork that should already work on Kinetic. I have not used it myself, so I'll have to trust other users but I understand that it works.
[..] with compatibility with moveit planner?
This I don't understand: the driver is separate from MoveIt in all aspects. It exposes a FollowJointTrajectory action interface, which MoveIt may use, but that is about as much interaction as there is between MoveIt and the driver.
Can you clarify what you mean with that last part of your question?
Maybe there are other solutions for computing boards with Trusty + Indigo, do you know some?
Intel seems to have a pretty powerfull x86 compatible board with the Up series. Perhaps that is something you could look in to.
Edit:
so maybe you could point me on what is critical in interfacing motion controller with ur_modern_driver
For MoveIt that is simple: a robot driver needs to expose a FollowJointTrajectory action interface (at least when using the default MoveIt trajectory execution infrastructure).
and what motion planners ROS users use
I'm not sure that is something I can answer. The typical go-to planner for serial manipulators is MoveIt, but there are plenty of other motion planning frameworks that cover similar and other use-cases.
I've looked in topic you mentioned, but it seems that UR3 users also met issues with this fork
According to the latest comment it would seem to work?
