Revert "Sletning af lektion fikset"

This reverts commit 257281ffdb9e5c7a90acbf862388b8ef0d12872a.
Revert "Fiksede at elever ikke blev tilføjet"

This reverts commit 49574157ed50e810a7d3610e02926895482162de.
Revert "seedData"

This reverts commit 2ab93b34befdd1d9166ad0cea9e5446a617d4a92.
Revert "UI ændringer"

This reverts commit aabf31187ba7554b98165312338babd3ec8b2f78.
Revert "Added a convenience method."

This reverts commit d12e10cb72b783fd7c6311646bc87f9a5e7cc888.
Revert "This should work. I need to test it, though."

This reverts commit 23997f6bad443f81fa155f2f166ecf4a0aa17fa0.