Feature Request: Easy Add/modify/manage new filiment

[cwestpha]

Would be great if we could add our own filament types within the GUI easily and then manage our types.

Just needs a few basic categories of material with basic settings, then you can modify temperatures, % rate, and perhaps a first layer modify.

example: Select template type PLA [it will pre-fill/suggest 210 for the extruder and 50 for print bed]

Name: Inland PLA print bed: 60 extruder: 205 extrusion rate: 100 First layer modifier checked Extrusion rate: 101 [it keeps the other settings the same]