In two places, we are joining label pieces by a '|' separator. We go
about it by putting the separator behind each entry, then removing the
trailing separator in a final fixup pass on the built string. For easier
reading, replace those occurrences by a new factored-out
'join_label_pieces' function.
Signed-off-by: Martin Povišer <povik@cutebit.org>
ad149cc42a