Change example code output to use backticks rather than indent

[caufang]

Right now when an "Example" is converted to markdown, it is done so using 4-space indents.

This works, but GitHub renders these as generic code blocks.

Code examples manually defined in the tutorial files are delimited using triple-backticks with the identifier openscad, which then presents with nice code coloring.

Indent

include <BOSL2/std.scad>
include <BOSL2/gears.scad>
spur_gear2d(diam_pitch=10, teeth=20, shaft_diam=5);

Backticks with openscad

include <BOSL2/std.scad>
include <BOSL2/gears.scad>
spur_gear2d(diam_pitch=10, teeth=20, shaft_diam=5);

My question is, would it be possible to change the function that outputs the code examples to use the backtick method?

I'm not verse in python so I can't attempt to do it myself and present a pull request.

[revarbat]

Should be simple to implement by altering code_block() in openscad_docsgen/target_githubwiki.py