Make the option for inline code within sections

[SimonBiggs]

Have a parameter called "run", the code written within run will run as if it was within that section.

This enables minimal code to be within the markdown file.

For example can have from package import * within a start section, and then have all the relevant start code within that package.

Then each section can just call a function which is defined within that package.

[SimonBiggs]

Have the parameter called code.

[SimonBiggs]

Complete