Using another thermistor than stock one

[luc-github]

DaVinci is not a RAMPS - because of usage of different resistor values on DaVinci, _NONE_ of generic tables will work:

• RAMPS:
  R1 =open
  R2 = 4.7K
• DaVinci Hotend
  R1(R29)= 1K
  R2(R27)= 4.7K
• DaVinci heated bed
  R1(R30)= open
  R2(R28)= 47K

So only 2 solutions :
1 - remove/change resistors on DaVinci board to be able to use generic tables
2 - create a custom table for the specific sensor - if you do it, feel free to push it to be integrated in custom FW to share with others.