test=develop

- Added rough profiling

- Profiled maxpool itself

- First draft of max seqpool optimization (is_test added)

- Added unit tests to seqpool

- Cosmetic fixes

- Fix to UT of Seq pool

Disabled grad checking for sequence max pool when is_test is set to True

-Cosmetic fix to comment

test=develop

- Fix to GPU build

test=develop

- yet another GPU fix for sequence max pool

- Fix to comment

test=develop

- Change to API of sequence_pool

test=develop

- Yet another API spec change

test=develop