Update mermaidAPI.js
Update mermaidAPI.js

-Added tables into the comments from mermaidAPI.md, to reflect documentation that I had added through a previous PR, #1509
-as per @knsv 's directions, added comments here.

-also found a list of parameters, who's documentation do not come out in the markdown file. I left them alone, but will be raising a separate issue, for others to review.
knsv/mermaid,knsv/mermaid