Added functional tests for the examples.

These won't run unless you pass the --runslow argument (which the Travis
config uses).  They should help us make sure that no pull requests or other
commits break any of the examples.  At least not in a way where the example
raises an exception.
Theano requires libblas.so
Try this combination of requirements (from Theano's own travis.yml)
Fix off by one error in training loop.
Using 'travis_wait' should help with 10min timeout.
Fix example tests that fail because of pylearn2 ImportError
Share data loading with mnist.py example.
Merge pull request #40 from dnouri/test-examples

Added functional tests for the examples.