This is the refactoring part of D8805 (should be no functional changes).
- exposes pose-related part of former 'get_constraints()' from
interface_templates.c to new ED_object_pose_constraint_list
- rename ED_object_constraint_list_from_context -->
ED_object_constraint_active_list
Also clarify comments on both of these.
ref T80464
ref https://developer.blender.org/D8805
- ED_object_constraint_list_from_constraint was get_constraint_lb
- ED_object_constraint_list_from_context was get_active_constraints
- ED_object_constraint_active_get was get_active_constraint
- ED_object_constraint_active_set was ED_object_constraint_set_active
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
This moves the `alembic`, `avi`, `collada`, and `usd` modules into a common
`io` directory.
This also cleans up some `#include "../../{somedir}/{somefile}.h"` by
adding `../../io/{somedir}` to `CMakeLists.txt` and then just using
`#include "{somefile}.h"`.
No functional changes.
