* add prob-grammar to notebook

* Update nlp.py

* add weighted choice

* tests for prob grammar + generation

* add test for weighted choice

* Update nlp.py

* Update README.md

* add powerset to utils

* add powerset test

* Create knowledge.py

* Create test_knowledge.py

* add header docstring to knowledge.py

* update learning docstring

* minor edits in knowledge.py

* Fixed truncated_svd

* Moved SVD algorithm to learning.py

* Delete test_grid.py

* Delete grid.ipynb

* Delete grid.py

* Move grid functions to utils

* Move grid tests to utils

* Update agents.py

* Update mdp.py

* Update search.py

* Create function to initialize random weights

* Add sigmoid derivative function

* Fix flake8 warnings

* Remove unnecessary #noqa

* Fix doctest

* Add Gaussian Function

* Added Tests

Add tests for Continuous Naive Bayes + Means/Standard Deviation

* Update learning.py

* Commenting Fix

* Add test for gaussian

* test for every class

* Update test_learning.py

* Round float results to make sure test passes

* Added test for FIFOQueue

* Updated FIFOQueue

* Updated FIFOQueue

* FIFOQueue using deque

* fixed flake8 warnings

added test for count() and mode()

* Add flake8 config file

* Fix flake8 for test files

Add InfixOps, refactor expo and Expr

Remove count_if, find_if, every, some, Struct; replace them with modern
Python equivalents.

Used tool 2to3 to finish the porting to Python 3 plus some fixes by
hand.