Fix test p33

Fix the test problem raised in gh-1405

NEWS.txt:
- Make MonitorMode use the default optimizers config and allow it to change used optimizers (Fred)
- lift Flatten/Reshape toward input on unary elemwise. (Fred)
   - This make the log(1-sigmoid) -> softplus opt being applied with a flatten/reshape in the middle.

Not NEWS.txt
- some a few remaning python 3.3.0 problem.
- Better error message.
- add inplace_elemwise_optimizer tag
- extend MonitorMode doc