This replaces header include guards with `#pragma once`.
A couple of include guards are not removed yet (e.g. `__RNA_TYPES_H__`),
because they are used in other places.
This patch has been generated by P1561 followed by `make format`.
Differential Revision: https://developer.blender.org/D8466
Surrounding includes with an 'extern "C"' block is not necessary anymore.
Also that made it harder to add any C++ code to some headers, or include headers
that have "optional" C++ code like `MEM_guardedalloc.h`.
I tested compilation on linux and windows (and got help from @LazyDodo).
If this still breaks compilation due to some linker error, the header containing
the symbol in question is probably missing an 'extern "C"' block.
Differential Revision: https://developer.blender.org/D7653
BF-admins agree to remove header information that isn't useful,
to reduce noise.
- BEGIN/END license blocks
Developers should add non license comments as separate comment blocks.
No need for separator text.
- Contributors
This is often invalid, outdated or misleading
especially when splitting files.
It's more useful to git-blame to find out who has developed the code.
See P901 for script to perform these edits.
