add keyCallback to main.cpp. Pressing ESC now ends the game. #40
fix glowutils package-adding in CMakeLists.txt #40
replace std::err messages with glow::fatal. #40

glow output:
* glow::info()
* glow:: debug()
* glow::warning()
* glow::critical()
* glow:: fatal()

see https://github.com/hpicgs/glow/blob/master/include/glow/logging.h
add F5 Key for reloading... does nothing at the moment. #40
add version check and output at start. #40