Blender Git Loki

POSELIB_OT_pose_add: only create keyframes for selected bones.

Previously the pose library used the WholeCharacter key set, which ignores
selection and add keys for almost all bones in the rig. This is a very
slow operation on complex rigs. With this patch, only selected bones are
keyed, defaulting to keying all bones when none are selected.

Note that this fixes the FIXME previously mentioned in the source.