Documentation Correct box.isEmpty method names (#8575)

* add method docs

intersectsBox method not documented.

* correct isEmpty method name

correct isEmpty method name

docs/api/math/Box2.html

@@ -151,7 +151,7 @@
 		*offset* units in 2D space.
 		</div>
 
-		<h3>[method:Boolean empty]()</h3>
+		<h3>[method:Boolean isEmpty]()</h3>
 		<div>
 		Returns true if this box includes zero points within its bounds.</br>
 		Note that a box with equal lower and upper bounds still includes one point, the

docs/api/math/Box3.html

@@ -159,7 +159,7 @@
 		*offset* units in 3D space.
 		</div>
 
-		<h3>[method:Boolean empty]()</h3>
+		<h3>[method:Boolean isEmpty]()</h3>
 		<div>
 		Returns true if this box includes zero points within its bounds.</br>
 		Note that a box with equal lower and upper bounds still includes one point, the