Version 0.8.6

Mechanics:

-The Rock can't spawn on the edges anymore, so you can always build a wall around it
-Enemies now only check for a new target if the old target is not in attack range

Balancing:

-The min time between waves is 180 sec now instead of 150 sec
-Reduced the health of the boss units from 30k to 20k

Bugfixes:

-If you destroyed a building that spawns units while it was build, the max amount of that unit still got lower
-Units couldn't enter towers
-If you destroyed a tower/wall the other walls/towers next to it did not update
-The eagles health was not visible