This is to prevent things such as sleep mode from printing anything on
the display when the reader is in USB MS.

Really, I could've just checked the battery state to know whether an USB
cable was plugged in...

(and I'm strongly hoping that it will continue like that too ;p)

Some spacer widgets are not required anymore because of the new
QTextEdit.

All's working! (Except maybe some layout shenaningans)

I still need to do some work, but it's ready to be merged into master.

Also, I fixed a dictionnary lookup issue where searching words in all
caps was impossible.

Works well, will have strange formatting is no InkBox version is known,
probably due to checkconfig_str_val being null if no  value is detected.