Add option to print sample riser together with main body

[codeTom]

Printing the sample riser and main body separately can cause slight deformation in the riser due to printing errors (edges detach from the bed) and it can be difficult to assemble so that it is exactly flat on the table. Depth of field is quite small with the 100x objective (~300nm), so it needs to be assembled to within ~0.1mm have the entire field in focus.
This adds an option to microscope_parameters to print the riser together with the main body and changes the shape of the clamp holes to trilinders.

[rwb27]

Thanks for this - I should have changed the clamp holes a while back!

My one question is whether it makes sense to include the riser on the microscope, or just to use the LS75 stage (which gives greater range of travel and less Z movement). Having a separate riser allows the LS65 body to be used with different heights of objective, and I have been pushed by a few folk to make this possible. Having the option to "bake in" the riser obviously doesn't break anything, I'm just curious if you think it has benefits over the LS75 body (which puts the sample in the same place)?

[codeTom]

I haven't tested the LS75, I had no idea that the difference is sample height (are the different versions described somewhere?). In this case the only real difference is either the footprint size or xy step size (is it larger or just taller?), so there is probably the no need for this, but it would be helpful to add the LS75 option to build instructions, no riser makes assembly easier.