Feature request

Is your feature request related to a problem? Please describe.
When we raise an internal error it may be quite some time before we get something in the dataflash log or in the mavlink stream. This makes it harder to correlate internal errors with codepaths.

Describe the solution you'd like
Emit a statustext and/or log message when we detect an internal error has

Hi, I got a problem similar to #804.

My bridge did not connect correctly.
I have followed the latest tutorial and build Apollo successfully today.
My apollo did not connect in the following step.

Launch bridge (inside docker container):
./scripts/bridge.sh

I would need to add sudo in order to start my bridge.sh.
After adding that, there was no information print out from the terminal.

void AStarExpansion::add(unsigned char* costs, float* potential, float prev_potential, int next_i, int end_x,  int end_y)
{
    .........
    if(costs[next_i]>=lethal_cost_ && !(unknown_ && costs[next_i]==costmap_2d::NO_INFORMATION))
        return;
    potential[next_i] = p_calc_->calculatePotential(potential, costs[next_i] + neutral_cost_, next_i, prev_potential);
     .......
}

The current webots keyboard device reports only whether keys are currently down. Even for fast typists, most keytaps leave the key down for multiple timesteps. In many instances, controller coders would like to trigger events once per key-tap (not once per timestep the key remains down), so they would like to know whether a key has just been pressed (or just been released), rather than just whet