Ancient versions of CMake required else(), endif(), and similar block
termination commands to have arguments matching the command starting the block.
This is no longer the preferred style.
* remove EIGEN_BUILD_TESTS and siblings
* add summary at the end of cmake run, hopefully not too verbose
* fix build of quaternion demo
* kill remnants of old binary library option
- much better coloring
- determine max number of iterations and choice between float and double
at runtime based on zoom level
- do draft renderings with increasing resolution before final rendering
