correctly merged from dev

src/core/BufferAttribute.js

@@ -4,6 +4,8 @@
 
 THREE.BufferAttribute = function ( array, itemSize ) {
 
+	this.uuid = THREE.Math.generateUUID();
+
 	this.array = array;
 	this.itemSize = itemSize;
 

src/core/InterleavedBufferAttribute.js

@@ -4,6 +4,8 @@
 
 THREE.InterleavedBufferAttribute = function ( interleavedBuffer, itemSize, offset ) {
 
+	this.uuid = THREE.Math.generateUUID();
+
 	this.data = interleavedBuffer;
 	this.itemSize = itemSize;
 	this.offset = offset;