Make a better trochoidal milling entry

[Siemenc]

I never used trochoidal milling but have been curious about it. It looks to me like the entry seems a bit harsh on the milling bit? Below is a screenshot of cutting at 5 mm depth. I'd expect the milling bit to make a spiral at the beginning before starting to cut around, whereas it seems like it moves in rather quickly

Also, perhaps we should make this setting as a bit more of an advanced setting or have some warning when using this or rename it. I think it's quite tempting to click on this when opening bark beetle for the first time thinking "Cool, high speed machining! Sounds great!" Whereas in wood for instance you get a higher speed of machining (as in, finish the piece, not the actual speed of the milling bit perhaps) by just cutting with a profile pass.

[JensDyvik]

I just fixed this in "Bark beetle 1.02 beta 4 - CNC milling - Rhino6.gh" published here: https://github.com/fellesverkstedet/Bark-beetle-parametric-toolpaths/tree/master/Development%20files

The error came from the this component changing input order in grasshopper for rhino6 from rhino5:

I agree that high speed machining is an advanced setting (and quite rarely used), so I moved the it to advanced 2D settings. This makes our main setting list shorter and less intimidating :)

I originally made the helix type an experimental variable diameter helix, which turned out to not be optimal:

I started work on making a classic constant diameter helix instead, but my concentration failed me. So for now I changed the default width factor of the trochoidal path from 2.3 to 2.01, which makes a near straight helix: