Add devices/xor-multidevice in example (#993)
Add devices/xor-multidevice in example (#993)



Former-commit-id: a5f230572688d36246b5937b41f42ebaadc207a4
xunzhang/dynet,xunzhang/dynet,clab/cnn,shuheik/dynet,clab/dynet,danielhers/dynet,chunyang-wen/dynet,danielhers/dynet,clab/dynet,shuheik/dynet,danielhers/dynet,danielhers/dynet,clab/dynet,clab/dynet,xunzhang/dynet,clab/cnn,shuheik/dynet,clab/cnn,shuheik/dynet,danielhers/dynet,danielhers/dynet,chunyang-wen/dynet,shuheik/dynet,clab/dynet,chunyang-wen/dynet,clab/dynet,shuheik/dynet,danielhers/dynet,xunzhang/dynet,chunyang-wen/dynet,shuheik/dynet,clab/dynet