extended help messages in gol
Added Comments to gol
heeded the advices in the pull request about the comments
added shorthand input -p for --periodic
removed solved question from Evolution.hpp
Exodus

All double slashes // left Simulation.hpp for a more cozy home.
setDevice hid itself in Environment.hpp, because it's an easily scared fella.
ifndef... died of old age and was superceeded by pragma once
number of neighbors bugfix
add short comment about directions, delete solved questions at same place
removed last questions
Merge pull request #305 from mxmlnkn/gol-comments

:+1 for your first pull request, big thanks!