Add Machinetutors (#2604)

README.md

@@ -1000,6 +1000,7 @@ API | Description | Auth | HTTPS | CORS |
 | [IPS Online](https://docs.identity.ps/docs) | Face and License Plate Anonymization | `apiKey` | Yes | Unknown |
 | [Irisnet](https://irisnet.de/api/) | Realtime content moderation API that blocks or blurs unwanted images in real-time | `apiKey` | Yes | Yes |
 | [Keen IO](https://keen.io/) | Data Analytics | `apiKey` | Yes | Unknown |
+| [Machinetutors](https://www.machinetutors.com/portfolio/MT_api.html) | AI Solutions: Video/Image Classification & Tagging, NSFW, Icon/Image/Audio Search, NLP | `apiKey` | Yes | Yes |
 | [NLP Cloud](https://nlpcloud.io) | NLP API using spaCy and transformers for NER, sentiments, classification, summarization, and more | `apiKey` | Yes | Unknown |
 | [OpenVisionAPI](https://openvisionapi.com) | Open source computer vision API based on open source models | No | Yes | Yes |
 | [Perspective](https://perspectiveapi.com) | NLP API to return probability that if text is toxic, obscene, insulting or threatening | `apiKey` | Yes | Unknown |