Replacing "position" settings for "route" settings

[BillyNate]

Hi @cloakedcode,

Thank you for all the effort to get the dockable probe into the main branch.
I recently put my own probe together using the README and videos of Annex-Engineering/Quickdraw_Probe. Once I got to the Klipper integration I noticed your PR and used this branch to get the probe working. Unfortunately I seem to have my dock set up in an unusual way so I couldn't get it completely right using only the approach_position, detach_position and dock_position. On top of this there seemed to be some unnecessary moves, making the attach/dock process only take longer.
This made me think I might not be the only one with an unusual dock setup and instead of adding more _position settings I decided to go with just two _route settings. This could prevent unsupported edge cases in the future and reduce code complexity.
My config now looks like this:

attach_route:
  95.5, -71.0
  95.5, -71.0, 0.5
  95.5, -81.0, 0.5
  95.5, -81.0, 10
dock_route:
  95.5, -81.0
  95.5, -81.0, 0.5
  95.5, -71.0, 0.5
  95.5, -71.0, 10

This moves the toolhead along the defined coordinates for attaching the probe and docking the probe respectively.

In the process of improving the attach and dock code I removed the vector and distance functions as they seemed no longer needed. Please let me know if I threw out the baby with the bathwater.

To keep the toolhead from crashing into anything I added a couple of _align_z()'s, just to be safe.

The code changes have only been tested on my own setup.

The documentation hasn't been updated to match the code changes yet. If the code changes are to be merged I will of course update the documentation as well.