2. add unit test library
3. remove useless comments
4. use js & css libs on the CDN

 * always do test on all test data
 * do test at the end of each pass if test_period=0, otherwise do test if test_period batches passed

out = w * input
where w is a parameter of size 1

Change-Id: Ife682d62323ceb1a20cbbf6269421b20a862d888