Our current header files don't have the `endif` comment. I don't really see the need unless you have an exorbitant amount of `endif`s. Also, nobody does this for code! Which is where it'd be more useful. (Except CMake, [which requires it](http://www.cmake.org/Wiki/CMake/Language_Syntax#IF_and_WHILE_control_the_flow.)... Oh my God...).