Add missing documentation for Skeleton3D methods

Adds description for get/set pose position/rotation/scale.

doc/classes/Skeleton3D.xml

@@ -126,18 +126,21 @@
 			<return type="Vector3" />
 			<param index="0" name="bone_idx" type="int" />
 			<description>
+				Returns the pose position of the bone at [param bone_idx]. The returned [Vector3] is in the local coordinate space of the [Skeleton3D] node.
 			</description>
 		</method>
 		<method name="get_bone_pose_rotation" qualifiers="const">
 			<return type="Quaternion" />
 			<param index="0" name="bone_idx" type="int" />
 			<description>
+				Returns the pose rotation of the bone at [param bone_idx]. The returned [Quaternion] is local to the bone with respect to the rotation of any parent bones.
 			</description>
 		</method>
 		<method name="get_bone_pose_scale" qualifiers="const">
 			<return type="Vector3" />
 			<param index="0" name="bone_idx" type="int" />
 			<description>
+				Returns the pose scale of the bone at [param bone_idx].
 			</description>
 		</method>
 		<method name="get_bone_rest" qualifiers="const">
@@ -265,20 +268,23 @@
 			<param index="0" name="bone_idx" type="int" />
 			<param index="1" name="position" type="Vector3" />
 			<description>
+				Sets the pose position of the bone at [param bone_idx] to [param position]. [param position] is a [Vector3] describing a position local to the [Skeleton3D] node.
 			</description>
 		</method>
 		<method name="set_bone_pose_rotation">
 			<return type="void" />
 			<param index="0" name="bone_idx" type="int" />
 			<param index="1" name="rotation" type="Quaternion" />
 			<description>
+				Sets the pose rotation of the bone at [param bone_idx] to [param rotation]. [param rotation] is a [Quaternion] describing a rotation in the bone's local coordinate space with respect to the rotation of any parent bones.
 			</description>
 		</method>
 		<method name="set_bone_pose_scale">
 			<return type="void" />
 			<param index="0" name="bone_idx" type="int" />
 			<param index="1" name="scale" type="Vector3" />
 			<description>
+				Sets the pose scale of the bone at [param bone_idx] to [param scale].
 			</description>
 		</method>
 		<method name="set_bone_rest">