add Mark II to menu
## Using Mycroft AI
* [Get Mycroft](using-mycroft-ai/get-mycroft/README.md)
+ * [Mark II](using-mycroft-ai/get-mycroft/mark-ii.md)
* [Mark 1](using-mycroft-ai/get-mycroft/mark-1.md)
* [Picroft](using-mycroft-ai/get-mycroft/picroft.md)
* [Linux](using-mycroft-ai/get-mycroft/linux.md)
