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
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This is often invalid, outdated or misleading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.
Drivers can use this to refer to the data which the driver is applied to,
useful for objects, bones, to avoid having to create a variable pointing to its self.
Support for driver variables that don't resolve to numbers, eg:
objects, bones, curves... etc.
Without this, Python expressions to access this data needed to use an absolute path from `bpy.data`,
however this is inconvenient, breaks easily (based on naming) and wouldn't set the dependencies correctly.
