Formatting for derivatives, adjoints, tangents etc. and some more matrix results?

[SteveBronder]

Looking over the collection of known derivatives etc. should that section have a header and a little, "Hey these are some common cases if you want to use these."?

It might also be nice to format them as a list

[Operation]:

• Derivative:
• Adjoint:
• Tangent:

There's also a few matrix algebra ops I can write here if you want them.

[bob-carpenter]

The intent is definitely a list of derivatives for functions. And yes, please fill them in and add a header. And add yourself as a co-author. I'd like to fill this out and get it "done" in some sense.