Feature: advanced inc subtensor grad

More readable error when compilation fails

improved doc for R_op
it all looks good. There is one line that I think does not respect PEP8 convention but I'll fix it in another pull request

Include the theano version in the compiledir.

added ability to use debug_assert without a message argument

fixed a bug where get_debug_values returns tuple(val) rather than val in

the case where it is fetching the value of only one variable

* No more forgetting to clear the cache!
* No more collisions when running multiple theano versions at once!

fixed error handling and doc for ifelse

(there was a problem that would reject a pair of branches
where one was shared and the other was not, regardless of
whether they had the same type)

Minor stuff

Also added a test to theano/tensor/test/test_inc_subtensor.py, but I am
unsure yet if it actually belongs there.

Updated NEWS.txt following scan change.

Fixed some tests

Temporary fix to a known bug for scan.

Added warning about sigmoid identification bug

Fix scan crash in recent change.

The code seems fine.,

Also updated NEWS.txt accordingly.

This fixes gh-302.

Test sigm opt

This fix the gpu scan optimization that was still passing an Apply as in the past.

Fixed bug in identification of sigmoid

It used to think that (any_constant + exp(x)) was equal to (1 + exp(x)).

Fix pycuda test