Plots: Change style, resize, add floating captions

[gagolews]

tikzDevice?

add grid in the background, overload

overload plot.window???

[gagolews]

• [x] fig.width, fig.height, out.width
• [x] new build chain with fig.caps (pandoc-fignos)
• [x] New illustrations in Ch 5
• [x] New illustrations in Ch 8
• [x] Ch 1
• [x] Ch 2
• [x] Ch 3
• [x] Ch 4
• [x] Ch 5
• [x] Ch 6
• [x] Ch 7
• [x] Ch 8
• [x] Ch 9
• [x] Do all plots have gray bg?
• [x] A
• [x] B
• [x] C
• [x] D

[gagolews]

should be merged with #20