feat: transition from TSLint to ESLint

mentioned in merge request projectmanagement!51 (merged)

mentioned in merge request api!50 (merged)

mentioned in merge request backend!95 (merged)

mentioned in merge request core!130 (merged)

mentioned in merge request core-tools!61 (merged)

mentioned in merge request proxy!21 (merged)

mentioned in merge request logger!11 (merged)

mentioned in merge request minimal-connector!18 (closed)

mentioned in merge request gitlab-api!6 (closed)

mentioned in merge request es-mapping-generator!3 (merged)

mentioned in merge request core!142 (merged)