feat(statistics): display some stats in the logs (#337)

* test: add more coverage

* docs: reorder and enhance typo

* docs(contributing): add more information about the npm scripts

* feat(statistics): add simple statistics

* feat(statistics): add more stats

* refactor(issues-processor): remove some options from the constructor

it should have been only useful for the tests

* feat(statistics): add stats for new stale or undo stale issues

* chore(rebase): handle rebase conflicts

src/main.ts

@@ -68,7 +68,8 @@ function _getAndValidateArgs(): IIssuesProcessorOptions {
     exemptPrAssignees: core.getInput('exempt-pr-assignees'),
     exemptAllAssignees: core.getInput('exempt-all-assignees') === 'true',
     exemptAllIssueAssignees: _toOptionalBoolean('exempt-all-issue-assignees'),
-    exemptAllPrAssignees: _toOptionalBoolean('exempt-all-pr-assignees')
+    exemptAllPrAssignees: _toOptionalBoolean('exempt-all-pr-assignees'),
+    enableStatistics: core.getInput('enable-statistics') === 'true'
   };
 
   for (const numberInput of [