Memory profiler in the new profiler

NEWS.txt:

- The new profiler now can profile the memory with the Theano flag profile_memory=True
- The ProfileMode now can't profile memory anymore and print a message about it.
- Now  we raise an error if we try to profile when the gpu is enabled if we didn't set correctly the env variable to force the driver to sync the kernel launch.
    - Otherwise the profile information are useless.