Switching out parameters in torus function

[odedstein]

This is in response to bug report #113 .
The parameters nr and nR are switched in the torus.py function.

[odedstein]

@sgsellan do you think this is the correct change to make? Or should I have changed the names of the parameters in the function declaration, but kept the old order, so as to not break old code?

[sgsellan]

Mmmm yeah, now that you mention it, it may be a better idea to keep backwards compatibility with old code (otherwise if I remember our rule correctly, that'd mean that we can only merge this PR for the next major release, 0.3.0)

[odedstein]

I was just going to make the change, but then the new order of parameters nr,nR,R,r would be weird unless we also change the order at the end of R,r to r,R (another breaking change).
Let's maybe just wait with merging this until we do 0.3.0 - it's a minor fix that should not be too hard to merge.

[sgsellan]

Sounds good to me then! Let's wait to merge this