[REQUEST] Skunk Score should be a "GPA score"-like letter based on a 0-100 scale

[etagwerker]

Before we start...:

• [x] I checked the documentation and didn't find this feature
• [x] I checked to make sure that this feature has not already been requested

Branch/Commit:

main branch.

Describe the feature:

As a new user I want to run skunk So that I can see a list of GPA scores per file

Problem:

As a new user I run skunk And then I see a list of skunk scores And I don't understand if my app is in great shape or horrible shape

Current:

+-----------------------------------------------------+----------------------------+----------------------------+----------------------------+----------------------------+----------------------------+
| file                                                | skunk_score                | churn_times_cost           | churn                      | cost                       | coverage                   |
+-----------------------------------------------------+----------------------------+----------------------------+----------------------------+----------------------------+----------------------------+
| lib/skunk/cli/commands/default.rb                   | 166.44                     | 1.6643999999999999         | 3                          | 0.5548                     | 0                          |
| lib/skunk/cli/application.rb                        | 139.2                      | 1.392                      | 3                          | 0.46399999999999997        | 0                          |
| lib/skunk/cli/command_factory.rb                    | 97.6                       | 0.976                      | 2                          | 0.488                      | 0                          |
| test/test_helper.rb                                 | 75.2                       | 0.752                      | 2                          | 0.376                      | 0                          |
| lib/skunk/rubycritic/analysed_module.rb             | 48.12                      | 1.7184                     | 2                          | 0.8592                     | 72.72727272727273          |
| test/lib/skunk/cli/commands/status_reporter_test.rb | 45.6                       | 0.456                      | 1                          | 0.456                      | 0                          |
| lib/skunk/cli/commands/base.rb                      | 29.52                      | 0.2952                     | 3                          | 0.0984                     | 0                          |
| lib/skunk/cli/commands/status_reporter.rb           | 8.0                        | 7.9956                     | 3                          | 2.6652                     | 100.0                      |
| test/lib/skunk/rubycritic/analysed_module_test.rb   | 2.63                       | 2.6312                     | 2                          | 1.3156                     | 100.0                      |
| lib/skunk.rb                                        | 0.0                        | 0.0                        | 2                          | 0.0                        | 0                          |
| lib/skunk/cli/options.rb                            | 0.0                        | 0.0                        | 2                          | 0.0                        | 0                          |
| lib/skunk/version.rb                                | 0.0                        | 0.0                        | 2                          | 0.0                        | 0                          |
| lib/skunk/cli/commands/help.rb                      | 0.0                        | 0.0                        | 2                          | 0.0                        | 0                          |
+-----------------------------------------------------+----------------------------+----------------------------+----------------------------+----------------------------+----------------------------+

Proposed:

+-----------------------------------------------------+----------------------------+----------------------------+----------------------------+----------------------------+----------------------------+
| file                                                | skunk_score                | churn_times_cost           | churn                      | cost                       | coverage                   |
+-----------------------------------------------------+----------------------------+----------------------------+----------------------------+----------------------------+----------------------------+
| lib/skunk/cli/commands/default.rb                   | F (7/100)                     | 1.6643999999999999         | 3                          | 0.5548                     | 0                          |
| lib/skunk/cli/application.rb                        | D (47/100)                      | 1.392                      | 3                          | 0.46399999999999997        | 0                          |
| lib/skunk/cli/command_factory.rb                    | A (93/100)                       | 0.976                      | 2                          | 0.488                      | 0                          |

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