15.4.2 Line Styles
Line styles are specified by the following properties:
linestyle- May be one of
"-"- Solid line. [default]
"--"- Dashed line.
":"- Dotted line.
"-."- A dash-dot line.
"none"- No line. Points will still be marked using the current Marker Style.
linewidth- A number specifying the width of the line. The default is 1. A value
of 2 is twice as wide as the default, etc.