Thread cutting script - WIP

 From:  Martin (MARTIN3D)
5451.62 In reply to 5451.61 
I attached a further optimized version of this script to the first post of this thread.

- The Cancel button works now correctly
- The thread length will no longer be automatically corrected to get full turns
- A rebuildcurve factory for the profile can be found in the script if someone wants to experiment. I didn't get it to work.