Surface plots

[arm61]

Write a section discussing 2d colourmap style plots.

@symmy596 this one is for you if you want it.

[symmy596]

Shotgun.

What do you have in mind? i.e. what is the context that will lead into this section of the book?

[arm61]

check out the Table of contents as it stands

[arm61]

Also have a look any @j-m-dean's final bullet point in #5 which is a nice idea

[arm61]

#50 is waiting on this apparently (just a heads up)

[arm61]

#53 has been merged, but I will add a chemistry example soon