include/lse/exception.h: add a todo for getting errno related error messages
include/gui/window/base.h: make the window initialization semaphore bound; change Ready method to wait_for_ready

 - make some virtual methods pure virtual methods as they should be
 - switch some class members to underscore naming instead of camel case
 - start to be more specific with which variables are class members and which are not
include/gui/window/base.h: make the pure virtual functions private; we also rename these methods to be more fitting to their purpose and underscore them instead of camel case

 - classes derived from GLWindow_Base (also, as I type that name I realize I should make it real camel case...) now post to init_sem when they are fully initialized and ready for rendering action
 - rename GLInit to setup_gl
 - add a method teardown_gl: this replaces the old destructor as calling a virtual function in a destructor is bad juju (and the compiler doesn't let you anyways)
     - this method is called explicitly by the engine after the quit message has been received
 - disable file logging for the time being, as we now get a nice console window in CLion anyways, and I also do not have the bin directory set up properly so the *.exe file (and thusly log files) end up in some random directory chosen by CLion
     - NOTE: can't seem to configure this through cmake, I think it is a bug in CLion
 - underscore a parameter name in the constructor of the windows implementation of GLWindow_Base