Update CONTRIBUTION.md with status from issue #27

(Note: it may be better to move issue #27 and this file into a wiki so that there aren't two places for the same information)

Author: redblobgames

CONTRIBUTION.md

@@ -4,7 +4,7 @@
 
 Thanks for considering contributing to `aima-javascript`! We are building *visualizations* of the concepts, problems, and solutions described in AIMA. Whether you are an aspiring [Google Summer of Code](https://summerofcode.withgoogle.com/organizations/5663121491361792/) student, or an independent contributor, here is a guide to how you can help:
 
-- First, read and understand the code to get a feel for the extent and the style.
+- First, read and understand the code to get a feel for how the visualizations are implemented.
 - Pick a chapter from the list below that's not already being worked on, and state your intent to work on it the [Division of work](https://github.com/aimacode/aima-javascript/issues/27) thread.
 - Alternatively, look at the [issues](https://github.com/aimacode/aima-javascript/issues) and pick one to work on.
 - Please squash all commits into a single commit.
@@ -13,29 +13,29 @@ Thanks for considering contributing to `aima-javascript`! We are building *visua
 
 | Chapter                                                                               | Status                      |
 | :----------------------------------------------------------------------------------:  | :-------------------------: |
-| [1-Introduction](/1-Introduction/)                                                      | In Progress                  |
+| [1-Introduction](/1-Introduction/)                                                      | In Progress?                 |
 | [2-Intelligent-Agents](/2-Intelligent-Agents)                                         | Completed                   |
 | [3-Solving-Problems-By-Searching](/3-Solving-Problems-By-Searching)                   | [In Progress](https://github.com/aimacode/aima-javascript/issues/57) |
 | [4-Beyond-Classical-Search](/4-Beyond-Classical-Search)                               | [In Progress](https://github.com/aimacode/aima-javascript/issues/58) |
-| [5-Adversarial-Search](/5-Adversarial-Search)                                         | In Progress                  |
-| [6-Constraint-Satisfaction-Problems](/6-Constraint-Satisfaction-Problems)             | Completed                   |
+| [5-Adversarial-Search](/5-Adversarial-Search)                                         | [In Progress](https://github.com/aimacode/aima-javascript/issues/72) |
+| [6-Constraint-Satisfaction-Problems](/6-Constraint-Satisfaction-Problems)             | In Progress?  |
 | [7-Logical-Agents](/7-Logical-Agents)                                                 | [In Progress](https://github.com/aimacode/aima-javascript/issues/65) |
 | [8-First-Order-Logic](/8-First-Order-Logic)                                           | Not implemented             |
 | [9-Inference-In-First-Order-Logic](/9-Inference-In-First-Order-Logic)                 | Not implemented             |
 | [10-Classical-Planning](/10-Classical-Planning)                                       | Not implemented             |
 | [11-Planning-And-Acting-In-The-Real-World](/11-Planning-And-Acting-In-The-Real-World) | Not implemented             |
 | [12-Knowledge-Representation](/12-Knowledge-Representation)                           | Not implemented             |
-| [13-Quantifying-Uncertainity](/13-Quantifying-Uncertainity)                           | In Progress                  |
+| [13-Quantifying-Uncertainity](/13-Quantifying-Uncertainity)                           | In Progress?                 |
 | [14-Probabilistic-Reasoning](/14-Probabilistic-Reasoning)                             | Not implemented             |
 | [15-Probabilistic-Reasoning-Over-Time](/15-Probabilistic-Reasoning-Over-Time)         | [In Progress](https://github.com/aimacode/aima-javascript/issues/59) |
 | [16-Making-Simple-Decisions](/16-Making-Simple-Decisions)                             | Not implemented             |
 | [17-Making-Complex-Decisions](/17-Making-Complex-Decisions)                           | Not implemented             |
 | [18-Learning-From-Examples](/18-Learning-From-Examples)                               | [In Progress](https://github.com/aimacode/aima-javascript/issues/60) |
-| [19-Knowledge-In-Learning](/19-Knowledge-In-Learning)                                 | Not implemented             |
+| [19-Knowledge-In-Learning](/19-Knowledge-In-Learning)                                 | [In Progress](https://github.com/aimacode/aima-javascript/issues/68) |
 | [20-Learning-Probabilistic-Models](/20-Learning-Probabilistic-Models)                 | Not implemented             |
-| [21-Reinforcement-Learning](/21-Reinforcement-Learning)                               | Not implemented             |
-| [22-Natural-Language-Processing](/22-Natural-Language-Processing)                     | In Progress                  |
-| [23-Natural-Language-For-Communication](/23-Natural-Language-For-Communication)       | In Progress                  |
+| [21-Reinforcement-Learning](/21-Reinforcement-Learning)                               | [In Progress](https://github.com/aimacode/aima-javascript/issues/62) |
+| [22-Natural-Language-Processing](/22-Natural-Language-Processing)                     | In Progress?                 |
+| [23-Natural-Language-For-Communication](/23-Natural-Language-For-Communication)       | In Progress?                 |
 | [24-Perception](/24-Perception)                                                       | Not implemented             |
 | [25-Robotics](/25-Robotics)                                                           | Not implemented             |
 | [26-Philosophical-Foundations](/26-Philosophical-Foundations)                         | Not implemented             |