Add a section for the Packet Lengths window. Use title case for the
column headers. Fix a button name and other issues elsewhere.
Change-Id: I339d56aa169158e0788acd02a897729205e9f50e
Reviewed-on: https://code.wireshark.org/review/35615
Reviewed-by: Gerald Combs <gerald@wireshark.org>
Gerald Combs