minor error fixes.

created a parameter size in the function leave_one_out(learner, dataset, size=None):

* Added testcase for agents.py

* spacing around commas was wrong

* Add Perceptron Section

* Add Perceptron Image

* updated games.ipynb with refactored games.py

* fixed typos in games.ipynb

* move play_game into games class

* display current state before prompting for action

* fixed player swap bug

* display available moves to human players

* make tests pass

Add DecisionTreeLearner, NeuralNetLearner and PerceptronLearner tests

* Update test_agents.py

pep8 changes, showed flake8 errors

* Update test_agents.py

* Update test_agents.py

* Update test_agents.py

* Update test_text.py

added missing whitespace after comma

* Update utils.py

added space after comma

* Update search.py

added space after comma

* Update probability.py

added space after comma

* Update learning.py

added space after comma

* Update planning.py

added double_tennis_problem

* Update rl.py

In the pseudocode figure 21.8, the first 'if' starts with argument 's', which is the previous state, not s1(i.e, the current state).

* Update search.py

the 'uniform_cost_search' in notebook 'search-4e.ipynb' resembles more to the pseudocode in book.

* Update search.py

* Update search.py

* Update search.py

* Bug fixing

* Spacing

* Fix NgramTextModel bug

* Add new tests for NgramTextModel

* Add NgramCharModel to text.py

* Update text.py

* Update

* Update utils.py

in pseudo code the sequence of arguments is   " WEIGHTED-SAMPLE-WITH-REPLACEMENT(N, S, W)"  

* Update utils.py

in pseudo code the sequence of arguments is " WEIGHTED-SAMPLE-WITH-REPLACEMENT(N, S, W)"  same must follow in function "particle_filtering" in the file probability.py

* Update learning.py

weight_sample_with_replacement sequence of args

* Update probability.py

 weighted_sample_with_replacement sequence of args

* Update search.py

* Update planning.py

added double_tennis_problem from chapter 11 , figure 11.10

* Update utils.py

added missing space after comma

* Update learning.py

added missing space after comma

* Update probability.py

added missing space after comma

* Update search.py

added missing space after comma

* Update planning.py

* Update planning.py

* Update planning.py

* Update planning.py

* Update planning.py

* Update planning.py

* Update test_agents.py

pep8 changes, showed flake8 errors

* Update test_agents.py

* Update test_agents.py

* Update test_agents.py

* Update test_text.py

added missing whitespace after comma

* Update utils.py

added space after comma

* Update search.py

added space after comma

* Update probability.py

added space after comma

* Update learning.py

added space after comma

* Update planning.py

added double_tennis_problem

* Update rl.py

In the pseudocode figure 21.8, the first 'if' starts with argument 's', which is the previous state, not s1(i.e, the current state).

* Update search.py

the 'uniform_cost_search' in notebook 'search-4e.ipynb' resembles more to the pseudocode in book.

* Update search.py

* Update search.py

* Update search.py

* Update README.md

* Update README.md

* Update README.md

* Update planning.py

* Update planning.py

added spaces after comma

* Update planning.py

* Update test_planning.py

added double_tennis_problem test

* Update test_planning.py

* Update logic.py

added fol_fc_ask from fig 9.3

* Update logic.py

* Update test_planning.py

* Bugfixing

* Test for "exclude"

* Update test_learning.py

* update_values

* Update games.ipynb

* Update intro.ipynb

* Update csp.ipynb

* Implement Topological Sort

- Implemented topological_sort
- Added auxiliary function build_topological
- Updated call to topological_sort

* Use defaultdict to build visited

* Added test

* Update csp.py

Skip first item of iteration

* Exclude test files from flake8 check

* Fix flake8 for main files

* Add flake8 check to build

* Added ShiftDecoder to notebook

* replaced code with psource

* fix spelling mistakes

* Adds hashable dict type

* Implemented permutation decoder

* added test for permutation decode

* Optimized permutationdecoder

* relaxed tests

* change string format

* Fixed string format

* Update learning.py

* Add Euclidean Distance

* Update learning.ipynb

* minor fix in notebook

* minor spacing in learning.py

* Added Euclidean Test