Change Student import to Sokrates standard

[Michiii11]

the device input box should have a popup that allows to search and select the devices

for now this should simply work via devices and ignore devicetypes

[elYanuki]

@Michiii11 does this actually have high priority? do we want to move forwards with the old web version? what did aberger tell you in that regard?

[elYanuki]

I cleaned up the verification a little, seems fine now