Use a good discriminator in header guards

[ikbenkous]

Include guard name collisions are no fun to debug. The core cpp guidelines recommend a 'good discriminator'.
https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#sf8-use-include-guards-for-all-header-files

Since paths are unique, I recommend the following syntax: KLOG_PATH_TO_FILE_H

#define ...	path
KLOG_DATABASE_H	src/database.h
KLOG_WIDGETS_MAP_MAPWIDGET_H	"src/widgets/map/mapwidget.h"

This way you won't have collisions of something like DATABASE_H between different projects or even inside of the project itself.
There could be multiple database.h files...

Let me know what you think. @ea4k

[ea4k]

I was not aware of it. Very good catch.
Thank you!