os 0.2.0

exec; both outputs on one pipe; appending and durability; measured volumes; place and exchange; owners, processors and available memory; a bounded read of input; output sent to the error stream; raw mode that keeps the interrupt; Windows facts. Over openkal 0.17.1 (openkal-linux 0.18.2, openkal-macos 0.15.1, openkal-windows 0.13.3); ok images over openkal-llvm-runtime 0.16.3 and openkal-tools 0.1.1 (#3).